After a period of stable operation of the online JAVA application, a JVM crash problem occurred

First, how was the problem discovered

The system is a scheduled task system that needs to execute business code at scheduled times. The business code mainly accesses MYSQL databases and caches for operations. Initially, the system logs were normal, but after running for a period of time overnight, the system automatically crashed, and the java process disappeared, leaving only the following crash log:

cat: /proc/1/environ: Permission denied
[admin@host-11-40-38-52 ~]$ more hs_err_pid231.log
#
# A fatal error has been detected by the Java Runtime Environment:
#
# SIGSEGV (0xb) at pc=0x00007f21a8c21325, pid=231, tid=139779725313792
#
# JRE version: Java(TM) SE Runtime Environment (8.0_20-b26) (build 1.8.0_20-b26)
# Java VM: Java HotSpot(TM) 64-Bit Server VM (25.20-b23 mixed mode linux-amd64 c
ompressed oops)
# Problematic frame:
# V  [libjvm.so+0x858325]  LoadKlassNode::make(PhaseGVN&, Node*, Node*, TypePtr
const*, TypeKlassPtr const*)+0x45
#
# Core dump written. Default location: /home/admin/core or core.231
#
# If you would like to submit a bug report, please visit:
#   http://bugreport.sun.com/bugreport/crash.jsp
#

---------------  T H R E A D  ---------------

Current thread (0x00007f21a4b80800):  JavaThread "C2 CompilerThread5" daemon [_t
hread_in_native, id=398, stack(0x00007f2100cfc000,0x00007f2100dfd000)]

siginfo: si_signo: 11 (SIGSEGV), si_code: 1 (SEGV_MAPERR), si_addr: 0x0000000000
000010

Registers:
RAX=0x00007f21a48fbab0, RBX=0x00007f21a48fe4b0, RCX=0x0000000000000000, RDX=0x00
000000fffffff4
RSP=0x00007f2100df9c40, RBP=0x00007f2100df9c80, RSI=0x00007f20b00e9050, RDI=0x00
007f1fe84e3650
R8 =0x00007f21a48fe4b0, R9 =0x00007f21a48fbab0, R10=0x00007f1ffc059d90, R11=0x00
007f21a8cf3560
R12=0x00007f2100dfad00, R13=0x00007f1fe84e3650, R14=0x00007f2100dfa100, R15=0x00
007f2100df9ee0
RIP=0x00007f21a8c21325, EFLAGS=0x0000000000010296, CSGSFS=0x0000000000000033, ER
R=0x0000000000000004
  TRAPNO=0x000000000000000e

Top of Stack: (sp=0x00007f2100df9c40)
0x00007f2100df9c40:   00007f20b00e9050 00007f21a48fbab0
0x00007f2100df9c50:   00007f2100df9c80 00007f21a48fe4b0
0x00007f2100df9c60:   00007f21a48fd440 00007f1fe84e3650
0x00007f2100df9c70:   00007f21a8cf3560 00007f2100df9ee0
0x00007f2100df9c80:   00007f2100df9da0 00007f21a891acb6
0x00007f2100df9c90:   00007f1ffc5122a0 00007f20b00301d0
0x00007f2100df9ca0:   00007f2100df9ce0 00007f1ffc933fc0
0x00007f2100df9cb0:   00007f2100df9ee0 00007f1ffc933fc0
0x00007f2100df9cc0:   00007f2100df9cf0 00007f21a89ac798
0x00007f2100df9cd0:   00007f2100df9cf0 00007f2100dfad00
0x00007f2100df9ce0:   0000000000000000 0000000000000002
0x00007f2100df9cf0:   00007f1ffc933fc0 00007f1ffc93ba68
0x00007f2100df9d00:   0000000000000000 00007f1ffc93ba68
0x00007f2100df9d10:   00007f2100df9d30 00007f2100000002
0x00007f2100df9d20:   00007f1ffc93b828 0000000000000000
0x00007f2100df9d30:   00007f20b0029970 0000000500000004
0x00007f2100df9d40:   00007f20b00301d0 00007f00000001b0
0x00007f2100df9d50:   000000c700000e83 00007f1ffc93b828
0x00007f2100df9d60:   00007f2100dfa100 00007f1ffc5126a0
0x00007f2100df9d70:   0000000000001019 00007f1ffc933fc0
0x00007f2100df9d80:   00007f2100df9ee0 00007f2100df9db0
0x00007f2100df9d90:   0000000000000000 00007f2100df9fd8
0x00007f2100df9da0:   00007f2100df9df0 00007f21a8cd1b0a
0x00007f2100df9db0:   00007f2100df9ee0 0000000000000000
0x00007f2100df9dc0:   00007f1f00000001 00007f2100df9ee0
0x00007f2100df9dd0:   0000000000000000 00007f2100df9ee0
0x00007f2100df9de0:   0000000000000000 00000000000001b0
0x00007f2100df9df0:   00007f2100df9e30 00007f21a8cd46f0
0x00007f2100df9e00:   00007f2100df9e30 00007f2100dfabd0
0x00007f2100df9e10:   00007f20b00fd458 00007f2100df9ee0
0x00007f2100df9e20:   000000000000001f 00007f1ffc936508
0x00007f2100df9e30:   00007f2100df9e80 00007f21a8cd4967

Instructions: (pc=0x00007f21a8c21325)
0x00007f21a8c21305:   c0 48 8b 02 4c 8b 67 10 49 89 fe 48 89 d7 ff 50
0x00007f21a8c21315:   28 8b 50 10 31 c9 83 ea 0e 83 fa 07 48 0f 42 c8
0x00007f21a8c21325:   8b 41 10 83 e8 10 83 f8 02 0f 87 9c 01 00 00 80
0x00007f21a8c21335:   79 32 00 0f 84 92 01 00 00 49 8b 06 49 89 df 48

Register to memory mapping:

RAX=0x00007f21a48fbab0 is an unknown value
RBX=0x00007f21a48fe4b0 is an unknown value
RCX=0x0000000000000000 is an unknown value
RDX=0x00000000fffffff4 is an unknown value
RSP=0x00007f2100df9c40 is pointing into the stack for thread: 0x00007f21a4b80800
RBP=0x00007f2100df9c80 is pointing into the stack for thread: 0x00007f21a4b80800
RSI=0x00007f20b00e9050 is an unknown value
RDI=0x00007f1fe84e3650 is an unknown value
R8 =0x00007f21a48fe4b0 is an unknown value
R9 =0x00007f21a48fbab0 is an unknown value
R10=0x00007f1ffc059d90 is an unknown value
R11=0x00007f21a8cf3560: <offset 0x92a560> in /home/export/servers/jdk1.8.0_20/jr
e/lib/amd64/server/libjvm.so at 0x00007f21a83c9000
R12=0x00007f2100dfad00 is pointing into the stack for thread: 0x00007f21a4b80800
R13=0x00007f1fe84e3650 is an unknown value
R14=0x00007f2100dfa100 is pointing into the stack for thread: 0x00007f21a4b80800
R15=0x00007f2100df9ee0 is pointing into the stack for thread: 0x00007f21a4b80800


Stack: [0x00007f2100cfc000,0x00007f2100dfd000],  sp=0x00007f2100df9c40,  free sp
ace=1015k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
V  [libjvm.so+0x858325]  LoadKlassNode::make(PhaseGVN&, Node*, Node*, TypePtr co
nst*, TypeKlassPtr const*)+0x45
V  [libjvm.so+0x551cb6]  Parse::catch_inline_exceptions(SafePointNode*)+0x946
V  [libjvm.so+0x908b0a]  Parse::do_exceptions()+0xba
V  [libjvm.so+0x90b6f0]  Parse::do_one_block()+0x180
V  [libjvm.so+0x90b967]  Parse::do_all_blocks()+0x127
V  [libjvm.so+0x90fd58]  Parse::Parse(JVMState*, ciMethod*, float, Parse*)+0x7b8
V  [libjvm.so+0x3e7d09]  ParseGenerator::generate(JVMState*, Parse*)+0x99
V  [libjvm.so+0x4931cc]  Compile::Compile(ciEnv*, C2Compiler*, ciMethod*, int, b
ool, bool, bool)+0x126c
V  [libjvm.so+0x3e67e8]  C2Compiler::compile_method(ciEnv*, ciMethod*, int)+0x19
8
V  [libjvm.so+0x49ba4a]  CompileBroker::invoke_compiler_on_method(CompileTask*)+
0xc8a
V  [libjvm.so+0x49e420]  CompileBroker::compiler_thread_loop()+0x620
V  [libjvm.so+0xa2990f]  JavaThread::thread_main_inner()+0xdf
V  [libjvm.so+0xa29a3c]  JavaThread::run()+0x11c
V  [libjvm.so+0x8e75f8]  java_start(Thread*)+0x108
C  [libpthread.so.0+0x7aa1]  start_thread+0xd1


Current CompileTask:
C2:43781461 13331   !   4       com.mysql.cj.NativeSession::execSQL (579 bytes)


---------------  P R O C E S S  ---------------

Java Threads: ( => current thread )
  0x00007f2010003800 JavaThread "qtp1589683045-1271" [_thread_blocked, id=142149]
, stack(0x00007f20fa995000,0x00007f20faa96000)]
  0x00007f1f58001800 JavaThread "Keep-Alive-Timer" daemon [_thread_blocked, id=1]
40557, stack(0x00007f20f830e000,0x00007f20f840f000)]
  0x00007f1fb005e800 JavaThread "logback-1" daemon [_thread_blocked, id=42936, state]
tack(0x00007f20fad99000,0x00007f20fae9a000)]
  0x00007f1f7c0c3000 JavaThread "logback-8" daemon [_thread_blocked, id=565, state]
ck(0x00007f20ea6f6000,0x00007f20ea7f7000)]
  0x00007f1f50003000 JavaThread "logback-7" daemon [_thread_blocked, id=521, state]
ck(0x00007f20fab97000,0x00007f20fac98000)]
  0x00007f1f10001000 JavaThread "logback-6" daemon [_thread_blocked, id=520, state]
ck(0x00007f20f002b000,0x00007f20f012c000)]
  0x00007f1f74004800 JavaThread "logback-5" daemon [_thread_blocked, id=519, state]
ck(0x00007f20f1830000,0x00007f20f1931000)]
  0x00007f1f5441d000 JavaThread "UMP-CheckFileRemovedThread" daemon [_thread_blocked, id=519, state]
cked, id=518, stack(0x00007f20ea7f7000,0x00007f20ea8f8000)]
  0x00007f1f5441b800 JavaThread "UMP-ProfilerFileUpdateThread" daemon [_thread_b
locked, id=517, stack(0x00007f20ea8f8000,0x00007f20ea9f9000)]
  0x00007f1f54419800 JavaThread "UMP-WriteLog2FileThread-jvmLogger" daemon [_thr
ead_blocked, id=516, stack(0x00007f20ea9f9000,0x00007f20eaafa000)]
  0x00007f1f54418000 JavaThread "UMP-WriteLog2FileThread-commonLogger" daemon [_
thread_blocked, id=515, stack(0x00007f20eaafa000,0x00007f20eabfb000)]
  0x00007f1f54416000 JavaThread "UMP-WriteLog2FileThread-tpLogger" daemon [_thre
ad_blocked, id=514, stack(0x00007f20eabfb000,0x00007f20eacfc000)]
  0x00007f1f5440f800 JavaThread "UMP-WriteLog2FileThread-bizLogger" daemon [_thr
ead_blocked, id=513, stack(0x00007f20eacfc000,0x00007f20eadfd000)]
  0x00007f1f54410800 JavaThread "UMP-WriteLog2FileThread-businessLogger" daemon
[_thread_blocked, id=512, stack(0x00007f20eadfd000,0x00007f20eaefe000)]
  0x00007f1f54408800 JavaThread "UMP-WriteLog2FileThread-aliveLogger" daemon [_t
hread_blocked, id=511, stack(0x00007f20eaefe000,0x00007f20eafff000)]
  0x00007f1f543da000 JavaThread "DatebookHikariCP2 housekeeper" daemon [_thread_
blocked, id=509, stack(0x00007f20f012c000,0x00007f20f022d000)]
  0x00007f1f543cf800 JavaThread "Jim-NioEventLoop - 1" daemon [_thread_in_native
, id=508, stack(0x00007f20f042d000,0x00007f20f052e000)]
  0x00007f1f54259800 JavaThread "SystemClock" daemon [_thread_blocked, id=507, s
tack(0x00007f20f172f000,0x00007f20f1830000)]
  0x00007f1f54216000 JavaThread "DatebookHikariCP4 housekeeper" daemon [_thread_
blocked, id=505, stack(0x00007f20f289f000,0x00007f20f29a0000)]
  0x00007f1f540b5000 JavaThread "UMP-WriteTPLogThread" daemon [_thread_blocked,
id=504, stack(0x00007f20fa490000,0x00007f20fa591000)]
  0x00007f1f50002000 JavaThread "logback-4" daemon [_thread_blocked, id=503, sta
ck(0x00007f20fa38f000,0x00007f20fa490000)]
  0x00007f1f74003000 JavaThread "logback-3" daemon [_thread_blocked, id=502, sta
ck(0x00007f20f29a0000,0x00007f20f2aa1000)]
  0x00007f21a4bc4000 JavaThread "http-nio-8001-Acceptor-0" daemon [_thread_in_na
tive, id=501, stack(0x00007f20f1d31000,)0x00007f20f1e32000)]
  0x00007f21a4bc2000 JavaThread "http-nio-8001-ClientPoller-1" daemon [_thread_i
n_native, id=500, stack(0x00007f20f1e32000,0x00007f20f1f33000)]
  0x00007f21a4bc0000 JavaThread "http-nio-8001-ClientPoller-0" daemon [_thread_i
n_native, id=499, stack(0x00007f20f1f33000,0x00007f20f2034000)]
  0x00007f21a4bbe800 JavaThread "http-nio-8001-exec-10" daemon [_thread_blocked,
 id=498, stack(0x00007f20f2034000,0x00007f20f2135000)]
  0x00007f21a4958800 JavaThread "http-nio-8001-exec-9" daemon [_thread_blocked,
id=497, stack(0x00007f20f2135000,0x00007f20f2236000)]
  0x00007f21a4956800 JavaThread "http-nio-8001-exec-8" daemon [_thread_blocked,
id=496, stack(0x00007f20f2236000,0x00007f20f2337000)]
  0x00007f21a4955000 JavaThread "http-nio-8001-exec-7" daemon [_thread_blocked,
id=495, stack(0x00007f20f2337000,0x00007f20f2438000)
  0x00007f21a4953800 JavaThread "http-nio-8001-exec-6" daemon [_thread_blocked,
id=494, stack(0x00007f20f2438000,0x00007f20f2539000)
  0x00007f21a4952000 JavaThread "http-nio-8001-exec-5" daemon [_thread_blocked,
id=493, stack(0x00007f20f2539000,0x00007f20f263a000)]
  0x00007f21a4b7e800 JavaThread "http-nio-8001-exec-4" daemon [_thread_blocked,
id=492, stack(0x00007f20f263a000,0x00007f20f273b000)]
  0x00007f21a4b7d000 JavaThread "http-nio-8001-exec-3" daemon [_thread_blocked,
id=491, stack(0x00007f20f273b000,0x00007f20f283c000)]
  0x00007f21a4b7b800 JavaThread "http-nio-8001-exec-2" daemon [_thread_blocked,
id=490, stack(0x00007f20f2cfd000,0x00007f20f2dfe000)]
  0x00007f21a4b7a000 JavaThread "http-nio-8001-exec-1" daemon [_thread_blocked,
id=489, stack(0x00007f20f2dfe000,0x00007f20f2eff000)]
  0x00007f21a4b78800 JavaThread "ContainerBackgroundProcessor[StandardEngine[Cat
alina]]" daemon [_thread_blocked, id=488, stack(0x00007f20f2aa1000,0x00007f20f2b)
a2000)]
  0x00007f1f7cb62800 JavaThread "scheduling-1" [_thread_in_native, id=487, stack
(0x00007f20f2ba2000,0x00007f20f2ca3000)]
  0x00007f1f74001000 JavaThread "logback-2" daemon [_thread_blocked, id=486, sta
ck(0x00007f20f2eff000,0x00007f20f3000000)]
  0x00007f1f7ca2b800 JavaThread "Jim-ConfigPoolingHeartbeat-1571143858733" daemo
n [_thread_in_native, id=442, stack(0x00007f20f800b000,0x00007f20f810c000)]
  0x00007f1f7c913800 JavaThread "mysql-cj-abandoned-connection-cleanup" daemon [
_thread_blocked, id=441, stack(0x00007f20f8833000,0x00007f20f8934000)]
  0x00007f1f7c7b8800 JavaThread "configurator-supervise" daemon [_thread_blocked
ck(0x00007f20f810c000,0x00007f20f820d000)]
  0x00007f1f7c7b7000 JavaThread "Thread-51" daemon [_thread_blocked, id=439, sta
ck(0x00007f20f820d000,0x00007f20f830e000)]
  0x00007f1f7c71e000 JavaThread "JSF-Future-Checker-CB-1-T-1" daemon [_thread_bl
ocked, id=436, stack(0x00007f20f8b34000,0x00007f20f8c35000)]
  0x00007f1f7c71d800 JavaThread "JSF-Future-Checker-0-T-1" daemon [_thread_block
ed, id=435, stack(0x00007f20f9bc2000,0x00007f20f9cc3000)]
  0x00007f1f7c3ba000 JavaThread "logback-1" daemon [_thread_blocked, id=433, sta
ck(0x00007f20f9635000,0x00007f20f9736000)]
  0x00007f21a4e27800 JavaThread "NioBlockingSelector.BlockPoller-1" daemon [_thr
ead_in_native, id=429, stack(0x00007f20fa591000,0x00007f20fa692000)]
  0x00007f2030001000 JavaThread "qtp1589683045-59 Selector15" [_thread_in_native
, id=414, stack(0x00007f20fb39f000,0x00007f20fb4a0000)]
  0x00007f21a4da0800 JavaThread "GC Daemon" daemon [_thread_blocked, id=413, sta
ck(0x00007f20fbafd000,0x00007f20fbbfe000)]
  0x00007f21a4baa000 JavaThread "Service Thread" daemon [_thread_blocked, id=411
, stack(0x00007f20fbeff000,0x00007f20fc000000)]
  0x00007f21a4b9a800 JavaThread "C1 CompilerThread17" daemon [_thread_blocked, i]
d=410, stack(0x00007f21000f0000,0x00007f21001f1000)]
  0x00007f21a4b98800 JavaThread "C1 CompilerThread16" daemon [_thread_blocked, i]
d=409, stack(0x00007f21001f1000,0x00007f21002f2000)]
  0x00007f21a4b96800 JavaThread "C1 CompilerThread15" daemon [_thread_blocked, i]
d=408, stack(0x00007f21002f2000,0x00007f21003f3000)]
  0x00007f21a4b94800 JavaThread "C1 CompilerThread14" daemon [_thread_blocked, i]
d=407, stack(0x00007f21003f3000,0x00007f21004f4000)]
  0x00007f21a4b92000 JavaThread "C1 CompilerThread13" daemon [_thread_blocked, i]
d=406, stack(0x00007f21004f4000,0x00007f21005f5000)]
  0x00007f21a4b90000 JavaThread "C1 CompilerThread12" daemon [_thread_blocked, i]
d=405, stack(0x00007f21005f5000,0x00007f21006f6000)]
  0x00007f21a4b8e000 JavaThread "C2 CompilerThread11" daemon [_thread_blocked, i]
d=404, stack(0x00007f21006f6000,0x00007f21007f7000)]
  0x00007f21a4b8b800 JavaThread "C2 CompilerThread10" daemon [_thread_blocked, i]
d=403, stack(0x00007f21007f7000,0x00007f21008f8000)]
  0x00007f21a4b89800 JavaThread "C2 CompilerThread9" daemon [_thread_blocked, id
=402, stack(0x00007f21008f8000,0x00007f21009f9000)]
  0x00007f21a4b87000 JavaThread "C2 CompilerThread8" daemon [_thread_blocked, id
=401, stack(0x00007f21009f9000,0x00007f2100afa000)
  0x00007f21a4b85000 JavaThread "C2 CompilerThread7" daemon [_thread_blocked, id
=400, stack(0x00007f2100afa000,0x00007f2100bfb000)]
  0x00007f21a4b83000 JavaThread "C2 CompilerThread6" daemon [_thread_blocked, id
=399, stack(0x00007f2100bfb000,0x00007f2100cfc000)]
=>0x00007f21a4b80800 JavaThread "C2 CompilerThread5" daemon [_thread_in_native,
id=398, stack(0x00007f2100cfc000,0x00007f2100dfd000)]
  0x00007f21a4b76800 JavaThread "C2 CompilerThread4" daemon [_thread_blocked, id
=397, stack(0x00007f2100dfd000,0x00007f2100efe000)]
  0x00007f21a4b74000 JavaThread "C2 CompilerThread3" daemon [_thread_blocked, id
=396, stack(0x00007f2100efe000,0x00007f2100fff000)]
  0x00007f21a4b72000 JavaThread "C2 CompilerThread2" daemon [_thread_blocked, id
=395, stack(0x00007f2108098000,0x00007f2108199000)]
  0x00007f21a4b6f800 JavaThread "C2 CompilerThread1" daemon [_thread_blocked, id
=394, stack(0x00007f2108199000,0x00007f210829a000)]
  0x00007f21a4b6e000 JavaThread "C2 CompilerThread0" daemon [_thread_blocked, id
=393, stack(0x00007f210829a000,0x00007f210839b000)]
  0x00007f21a4b6b000 JavaThread "qtp1589683045-38 Selector14" [_thread_in_native
, id=392, stack(0x00007f210839b000,0x00007f210849c000)]
  0x00007f21a4b69000 JavaThread "qtp1589683045-37 Selector13" [_thread_in_native
, id=391, stack(0x00007f210849c000,0x00007f210859d000)]
  0x00007f21a4b67000 JavaThread "qtp1589683045-36 Selector12" [_thread_in_native
, id=390, stack(0x00007f210859d000,0x00007f210869e000)]
  0x00007f21a4b65000 JavaThread "qtp1589683045-35 Selector11" [_thread_in_native
, id=389, stack(0x00007f210869e000,0x00007f210879f000)]
  0x00007f21a4b62800 JavaThread "qtp1589683045-34 Selector10" [_thread_in_native
, id=388, stack(0x00007f210879f000,0x00007f21088a0000)]
  0x00007f21a4b60800 JavaThread "qtp1589683045-33 Selector9" [_thread_in_native,
 id=387, stack(0x00007f21088a0000,0x00007f21089a1000)]
  0x00007f21a4b5e800 JavaThread "qtp1589683045-32 Selector8" [_thread_in_native,
 id=386, stack(0x00007f21089a1000,0x00007f2108aa2000)]
  0x00007f21a4b5c800 JavaThread "qtp1589683045-31 Selector7" [_thread_in_native,
 id=385, stack(0x00007f2108aa2000,0x00007f2108ba3000)]
  0x00007f21a4b5a800 JavaThread "qtp1589683045-30 Selector6" [_thread_in_native,
 id=384, stack(0x00007f2108ba3000,0x00007f2108ca4000)]
  0x00007f21a4b58800 JavaThread "qtp1589683045-29 Selector5" [_thread_in_native,
 id=383, stack(0x00007f2108ca4000,0x00007f2108da5000)]
  0x00007f21a4b56800 JavaThread "qtp1589683045-28 Selector4" [_thread_in_native,
 id=382, stack(0x00007f2108da5000,0x00007f2108ea6000)
  0x00007f21a4b54800 JavaThread "qtp1589683045-27 Selector3" [_thread_in_native,
 id=381, stack(0x00007f2108ea6000,0x00007f2108fa7000)
  0x00007f21a4b52800 JavaThread "qtp1589683045-26 Selector2" [_thread_in_native,
 id=380, stack(0x00007f2108fa7000,0x00007f21090a8000)
  0x00007f21a4b50800 JavaThread "qtp1589683045-25 Selector1" [_thread_in_native,
 id=379, stack(0x00007f21090a8000,0x00007f21091a9000)
  0x00007f21a49ad800 JavaThread "qtp1589683045-24 Selector0" [_thread_in_native,
 id=378, stack(0x00007f21091a9000,0x00007f21092aa000)
  0x00007f21a49ac000 JavaThread "qtp1589683045-23 Acceptor15 SelectChannelConnec
tor@0.0.0.0:7001 STARTING" [_thread_blocked, id=377, stack(0x00007f21092aa000,0x
00007f21093ab000)
  0x00007f21a49a8800 JavaThread "qtp1589683045-22 Acceptor14 SelectChannelConnec
tor@0.0.0.0:7001 STARTING" [_thread_blocked, id=376, stack(0x00007f21093ab000,0x
00007f21094ac000)
  0x00007f21a49a6800 JavaThread "qtp1589683045-21 Acceptor13 SelectChannelConnec
tor@0.0.0.0:7001 STARTING" [_thread_blocked, id=375, stack(0x00007f21094ac000,0x
00007f21095ad000)]
  0x00007f21a49a4800 JavaThread "qtp1589683045-20 Acceptor12 SelectChannelConnec
tor@0.0.0.0:7001 STARTING" [_thread_blocked, id=374, stack(0x00007f21095ad000,0x
00007f21096ae000)]
  0x00007f21a49a2800 JavaThread "qtp1589683045-19 Acceptor11 SelectChannelConnec
tor@0.0.0.0:7001 STARTING" [_thread_blocked, id=373, stack(0x00007f21096ae000,0x
00007f21097af000)]
  0x00007f21a49a0800 JavaThread "qtp1589683045-18 Acceptor10 SelectChannelConnec
tor@0.0.0.0:7001 STARTING" [_thread_blocked, id=372, stack(0x00007f21097af000,0x
00007f21098b0000)]
  0x00007f21a499e800 JavaThread "qtp1589683045-17 Acceptor9 SelectChannelConnect
or@0.0.0.0:7001 STARTING" [_thread_blocked, id=371, stack(0x00007f21098b0000,0x0
0007f21099b1000)]
  0x00007f21a499d800 JavaThread "qtp1589683045-16 Acceptor7 SelectChannelConnect
or@0.0.0.0:7001 STARTING" [_thread_in_native, id=370, stack(0x00007f21099b1000,0
x00007f2109ab2000)]
  0x00007f21a4994800 JavaThread "qtp1589683045-15 Acceptor8 SelectChannelConnect
or@0.0.0.0:7001 STARTING" [_thread_blocked, id=369, stack(0x00007f2109ab2000,0x0
0007f2109bb3000)]
  0x00007f21a4992800 JavaThread "qtp1589683045-14 Acceptor6 SelectChannelConnect
or@0.0.0.0:7001 STARTING" [_thread_blocked, id=368, stack(0x00007f2109bb3000,0x0
0007f2109cb4000)]
  0x00007f21a4990800 JavaThread "qtp1589683045-13 Acceptor3 SelectChannelConnect
or@0.0.0.0:7001 STARTING" [_thread_blocked, id=367, stack(0x00007f2109cb4000,0x0
0007f2109db5000)]
  0x00007f21a498e800 JavaThread "qtp1589683045-12 Acceptor2 SelectChannelConnect
or@0.0.0.0:7001 STARTING" [_thread_blocked, id=366, stack(0x00007f2109db5000,0x0
0007f2109eb6000)]
  0x00007f21a498c800 JavaThread "qtp1589683045-11 Acceptor5 SelectChannelConnect
or@0.0.0.0:7001 STARTING" [_thread_blocked, id=365, stack(0x00007f2109eb6000,0x0
0007f2109fb7000)]
  0x00007f21a498a800 JavaThread "qtp1589683045-10 Acceptor4 SelectChannelConnect
or@0.0.0.0:7001 STARTING" [_thread_blocked, id=364, stack(0x00007f2109fb7000,0x0
0007f210a0b8000)]
  0x00007f21a4988800 JavaThread "qtp1589683045-9 Acceptor1 SelectChannelConnecto
r@0.0.0.0:7001 STARTING" [_thread_blocked, id=363, stack(0x00007f210a0b8000,0x00
007f210a1b9000)]
  0x00007f21a4987000 JavaThread "qtp1589683045-8 Acceptor0 SelectChannelConnecto
r@0.0.0.0:7001 STARTING" [_thread_blocked, id=362, stack(0x00007f210a1b9000,0x00
007f210a2ba000)]
  0x00007f21a497c000 JavaThread "HashSessionScavenger-0" daemon [_thread_blocked
, id=361, stack(0x00007f210a2ba000,0x00007f210a3bb000)]
  0x00007f21a46a5800 JavaThread "Signal Dispatcher" daemon [_thread_blocked, id=
360, stack(0x00007f210abec000,0x00007f210aced000)]
  0x00007f21a4676800 JavaThread "Finalizer" daemon [_thread_blocked, id=359, sta
ck(0x00007f210aced000,0x00007f210adee000)]
  0x00007f21a4674800 JavaThread "Reference Handler" daemon [_thread_blocked, id=
358, stack(0x00007f210adee000,0x00007f210aeef000)]
  0x00007f21a400b000 JavaThread "main" [_thread_in_native, id=243, stack(0x00007
f21a9e2b000,0x00007f21a9f2c000)]

Other Threads:
  0x00007f21a466d800 VMThread [stack: 0x00007f210aeef000,0x00007f210aff0000] [id
=355]
  0x00007f21a4bad000 WatcherThread [stack: 0x00007f20fbdfe000,0x00007f20fbeff000
] [id=412]

VM state: not at safepoint (normal execution)

VM Mutex/Monitor currently owned by a thread: None

Heap:
 PSYoungGen total 1305088K, used 1009509K [0x000000076ab00000, 0x00000007c0
000000, 0x00000007c0000000)
  eden space 1209856K, 82% used [0x000000076ab00000,0x00000007a7b58fa8,0x0000000
7b4880000)
  from space 95232K, 10% used [0x00000007ba300000,0x00000007bac804c0,0x00000007c
0000000)
  to space 92672K, 0% used [0x00000007b4880000,0x00000007b4880000,0x00000007ba
300000)
 ParOldGen total 2796544K, used 50182K [0x00000006c0000000, 0x000000076ab0
0000, 0x000000076ab00000)
  object space 2796544K, 1% used [0x00000006c0000000,0x00000006c31019c8,0x000000
076ab00000)
 Metaspace used 69176K, capacity 71536K, committed 71808K, reserved 111206
4K
  class space used 7973K, capacity 8461K, committed 8576K, reserved 1048576K

Card table byte_map: [0x00007f21937c9000,0x00007f2193fca000] byte_map_base: 0x00
007f21901c9000

Marking Bits: (ParMarkBitMap*) 0x00007f21a9320ac0
 Begin Bits: [0x00007f20a4000000, 0x00007f20a8000000)
 End Bits: [0x00007f20a8000000, 0x00007f20ac000000)

Polling page: 0x00007f21a9f33000

CodeCache: size=245760Kb used=45854Kb max_used=45878Kb free=199905Kb
 bounds [0x00007f219438a000, 0x00007f219709a000, 0x00007f21a338a000]
 total_blobs=11396 nmethods=10825 adapters=479
 compilation: enabled

Compilation events (10 events):
Event: 42853.758 Thread 0x00007f21a4b98800 nmethod 13322 0x00007f21967d2650 code
 [0x00007f21967d2840, 0x00007f21967d30f8]
Event: 42941.467 Thread 0x00007f21a4b89800 13327 4 java.util.concurrent
ScheduledThreadPoolExecutor$DelayedWorkQueue::add (9 bytes)
Event: 42941.467 Thread 0x00007f21a4b87000 13328 ! 4 java.util.concurrent
ScheduledThreadPoolExecutor$DelayedWorkQueue::offer (124 bytes)
Event: 42941.467 Thread 0x00007f21a4b80800 13329 4 java.util.concurrent
ent.ThreadPoolExecutor::ensurePrestart (41 bytes)
Event: 42941.469 Thread 0x00007f21a4b80800 nmethod 13329 0x00007f21967d0dd0 code
 [0x00007f21967d0f20, 0x00007f21967d0ff8]
Event: 42941.493 Thread 0x00007f21a4b87000 nmethod 13328 0x00007f219708a2d0 code
 [0x00007f219708a540, 0x00007f219708b680]
Event: 42941.493 Thread 0x00007f21a4b89800 nmethod 13327 0x00007f2197070390 code
 [0x00007f2197070600, 0x00007f2197071700]
Event: 43421.467 Thread 0x00007f21a4b74000 13330       4       com.mysql.cj.resu
lt.DefaultColumnDefinition::<init> (41 bytes)
Event: 43421.469 Thread 0x00007f21a4b74000 nmethod 13330 0x00007f2196854910 code
 [0x00007f2196854a60, 0x00007f2196854b78]
Event: 43781.449 Thread 0x00007f21a4b80800 13331   !   4       com.mysql.cj.Nati
veSession::execSQL (579 bytes)

GC Heap History (10 events):
Event: 2901.101 GC heap before
{Heap before GC invocations=9 (full 3):
 PSYoungGen total 1223168K, used 1048576K [0x000000076ab00000, 0x00000007c0
000000, 0x00000007c0000000)
  eden space 1048576K, 100% used [0x000000076ab00000,0x00000007aab00000,0x000000
07aab00000)
  from space 174592K, 0% used [0x00000007aab00000,0x00000007aab00000,0x00000007b
5580000)
  to space 101376K, 0% used [0x00000007b9d00000,0x00000007b9d00000,0x00000007c
0000000)
 ParOldGen total 2796544K, used 50126K [0x00000006c0000000, 0x000000076ab0
0000, 0x000000076ab00000)
  object space 2796544K, 1% used [0x00000006c0000000,0x00000006c30f39b8,0x000000
076ab00000)
 Metaspace used 67592K, capacity 69946K, committed 70144K, reserved 111206
4K
  class space used 7943K, capacity 8414K, committed 8448K, reserved 1048576K
Event: 2901.121 GC heap after
Heap after GC invocations=9 (full 3):
 PSYoungGen total 1296896K, used 14251K [0x000000076ab00000, 0x00000007c000
0000, 0x00000007c0000000)
  eden space 1195520K, 0% used [0x000000076ab00000,0x000000076ab00000,0x00000007
b3a80000)
  from space 101376K, 14% used [0x00000007b9d00000,0x00000007baaeaf98,0x00000007
b0000000)
  to space 100864K, 0% used [0x00000007b3a80000,0x00000007b3a80000,0x00000007b
9d00000)
 ParOldGen total 2796544K, used 50150K [0x00000006c0000000, 0x000000076ab0
0000, 0x000000076ab00000)
  object space 2796544K, 1% used [0x00000006c0000000,0x00000006c30f99c8,0x000000
076ab00000)
 Metaspace used 67592K, capacity 69946K, committed 70144K, reserved 111206
4K
  class space used 7943K, capacity 8414K, committed 8448K, reserved 1048576K
}
Event: 10747.104 GC heap before
{Heap before GC invocations=10 (full 3):}
 PSYoungGen total 1296896K, used 1209771K [0x000000076ab00000, 0x00000007c0
000000, 0x00000007c0000000)
  eden space 1195520K, 100% used [0x000000076ab00000,0x00000007b3a80000,0x000000
07b3a80000)
  from space 101376K, 14% used [0x00000007b9d00000,0x00000007baaeaf98,0x00000007
b0000000)
  to space 100864K, 0% used [0x00000007b3a80000,0x00000007b3a80000,0x00000007
9d00000)
 ParOldGen total 2796544K, used 50150K [0x00000006c0000000, 0x000000076ab0
0000, 0x000000076ab00000)
  object space 2796544K 1% used [0x00000006c0000000,0x00000006c30f99c8,0x000000
076ab00000)
 Metaspace used 68322K, capacity 70672K, committed 70912K, reserved 111206
4K
  class space used 7963K, capacity 8423K, committed 8448K, reserved 1048576K
Event: 10747.119 GC heap after
Heap after GC invocations=10 (full 3):
 PSYoungGen total 1296384K, used 10324K [0x000000076ab00000, 0x00000007c000
0000, 0x00000007c0000000)
  eden space 1195520K, 0% used [0x000000076ab00000,0x000000076ab00000,0x00000007
b3a80000)
  from space 100864K, 10% used [0x00000007b3a80000,0x00000007b44951c8,0x00000007
b9d00000)
  to space 99840K, 0% used [0x00000007b9e80000,0x00000007b9e80000,0x00000007c0
000000)
 ParOldGen total 2796544K, used 50158K [0x00000006c0000000, 0x000000076ab0
0000, 0x000000076ab00000)
  object space 2796544K, 1% used [0x00000006c0000000,0x00000006c30fb9c8,0x000000
076ab00000)
 Metaspace used 68322K, capacity 70672K, committed 70912K, reserved 111206
4K
  class space used 7963K capacity 8423K, committed 8448K, reserved 1048576K
}
Event: 18892.422 GC heap before
{Heap before GC invocations=11 (full 3):
 PSYoungGen total 1296384K, used 1205844K [0x000000076ab00000, 0x00000007c0
000000, 0x00000007c0000000)
  eden space 1195520K, 100% used [0x000000076ab00000,0x00000007b3a80000,0x000000
07b3a80000)
  from space 100864K, 10% used [0x00000007b3a80000,0x00000007b44951c8,0x00000007
b9d00000)
  to space 99840K, 0% used [0x00000007b9e80000,0x00000007b9e80000,0x00000007c0
000000)
 ParOldGen total 2796544K, used 50158K [0x00000006c0000000, 0x000000076ab0
0000, 0x000000076ab00000)
  object space 2796544K, 1% used [0x00000006c0000000,0x00000006c30fb9c8,0x000000
076ab00000)
 Metaspace used 68759K, capacity 71020K, committed 71168K, reserved 111206
4K
  class space used 7970K, capacity 8429K, committed 8448K, reserved 1048576K
Event: 18892.439 GC heap after
Heap after GC invocations=11 (full 3):
 PSYoungGen total 1299968K, used 9668K [0x000000076ab00000, 0x00000007c0000
000, 0x00000007c0000000)
  eden space 1200128K, 0% used [0x000000076ab00000,0x000000076ab00000,0x00000007
b3f00000)
  from space 99840K, 9% used [0x00000007b9e80000,0x00000007ba7f11f8,0x00000007c0
000000)
  to space 97792K, 0% used [0x00000007b3f00000,0x00000007b3f00000,0x00000007b9
e80000)
 ParOldGen total 2796544K, used 50166K [0x00000006c0000000, 0x000000076ab0
0000, 0x000000076ab00000)
  object space 2796544K, 1% used [0x00000006c0000000,0x00000006c30fd9c8,0x000000
076ab00000)
 Metaspace used 68759K, capacity 71020K, committed 71168K, reserved 111206
4K
  class space used 7970K, capacity 8429K, committed 8448K, reserved 1048576K
}
Event: 27681.725 GC heap before
{Heap before GC invocations=12 (full 3):
 PSYoungGen total 1299968K, used 1209796K [0x000000076ab00000, 0x00000007c0
000000, 0x00000007c0000000)
  eden space 1200128K, 100% used [0x000000076ab00000,0x00000007b3f00000,0x000000
07b3f00000)
  from space 99840K, 9% used [0x00000007b9e80000,0x00000007ba7f11f8,0x00000007c0
000000)
  to space 97792K, 0% used [0x00000007b3f00000,0x00000007b3f00000,0x00000007b9
e80000)
 ParOldGen total 2796544K, used 50166K [0x00000006c0000000, 0x000000076ab0
0000, 0x000000076ab00000)
  object space 2796544K, 1% used [0x00000006c0000000,0x00000006c30fd9c8,0x000000
076ab00000)
 Metaspace used 68898K, capacity 71216K, committed 71424K, reserved 111206
4K
  class space used 7971K, capacity 8429K, committed 8448K, reserved 1048576K
Event: 27681.740 GC heap after
Heap after GC invocations=12 (full 3):
 PSYoungGen total 1297920K, used 9809K [0x000000076ab00000, 0x00000007c0000
000, 0x00000007c0000000)
  eden space 1200128K, 0% used [0x000000076ab00000,0x000000076ab00000,0x00000007
b3f00000)
  from space 97792K, 10% used [0x00000007b3f00000,0x00000007b48944d0,0x00000007b
9e80000)
  to   space 95232K, 0% used [0x00000007ba300000,0x00000007ba300000,0x00000007c0
000000)
 ParOldGen       total 2796544K, used 50174K [0x00000006c0000000, 0x000000076ab0
0000, 0x000000076ab00000)
  object space 2796544K, 1% used [0x00000006c0000000,0x00000006c30ff9c8,0x000000
076ab00000)
 Metaspace used 68898K, capacity 71216K, committed 71424K, reserved 111206
4K
  class space used 7971K, capacity 8429K, committed 8448K, reserved 1048576K
}
Event: 36688.570 GC heap before
{Heap before GC invocations=13 (full 3):
 PSYoungGen      total 1297920K, used 1209937K [0x000000076ab00000, 0x00000007c0
000000, 0x00000007c0000000)
  eden space 1200128K, 100% used [0x000000076ab00000,0x00000007b3f00000,0x000000
07b3f00000)
  from space 97792K, 10% used [0x00000007b3f00000,0x00000007b48944d0,0x00000007b
9e80000)
  to   space 95232K, 0% used [0x00000007ba300000,0x00000007ba300000,0x00000007c0
000000)
 ParOldGen       total 2796544K, used 50174K [0x00000006c0000000, 0x000000076ab0
0000, 0x000000076ab00000)
  object space 2796544K, 1% used [0x00000006c0000000,0x00000006c30ff9c8,0x000000
076ab00000)
 Metaspace used 69049K, capacity 71376K, committed 71552K, reserved 111206
4K
  class space    used 7972K, capacity 8461K, committed 8576K, reserved 1048576K
Event: 36688.584 GC heap after
Heap after GC invocations=13 (full 3):
 PSYoungGen      total 1305088K, used 9729K [0x000000076ab00000, 0x00000007c0000
000, 0x00000007c0000000)
  eden space 1209856K, 0% used [0x000000076ab00000,0x000000076ab00000,0x00000007
b4880000)
  from space 95232K, 10% used [0x00000007ba300000,0x00000007bac804c0,0x00000007c
0000000)
  to space 92672K, 0% used [0x00000007b4880000,0x00000007b4880000,0x00000007ba
300000)
 ParOldGen total 2796544K, used 50182K [0x00000006c0000000, 0x000000076ab0
0000, 0x000000076ab00000)
  object space 2796544K, 1% used [0x00000006c0000000,0x00000006c31019c8,0x000000
076ab00000)
 Metaspace used 69049K, capacity 71376K, committed 71552K, reserved 111206
4K
  class space used 7972K, capacity 8461K, committed 8576K, reserved 1048576K
}

Deoptimization events (10 events):
Event: 12281.446 Thread 0x00007f1f7cb62800 Uncommon trap: reason=unreached action
n=reinterpret pc=0x00007f2195f964f0 method=com.mysql.cj.result.DefaultColumnDefi
nition.findColumn(Ljava/lang/String;ZI)I @ 28
Event: 13726.994 Thread 0x00007f1f74001000 Uncommon trap: reason=unreached action
n=reinterpret pc=0x00007f2196c65958 method=java.util.concurrent.ScheduledThreadP
oolExecutor$DelayedWorkQueue.take()Ljava/util/concurrent/RunnableScheduledFuture
; @ 59
Event: 14951.443 Thread 0x00007f1f7cb62800 Uncommon trap: reason=range_check action
ion=make_not_entrant pc=0x00007f21966609f0 method=java.util.DualPivotQuicksort.sort([IIIZ)V
ort([IIIZ)V @ 56
Event: 14951.507 Thread 0x00007f1f543cf800 Uncommon trap: reason=unreached action
n=reinterpret pc=0x00007f2196a0fad0 method=io.netty.util.internal.shaded.org.jct
ools.queues.MpscArrayQueue.poll()Ljava/lang/Object; @ 28
Event: 14951.507 Thread 0x00007f1f543cf800 Uncommon trap: reason=unreached action
n=reinterpret pc=0x00007f2196196cf8 method=io.netty.buffer.PooledByteBuf.internalNioBuffer()Ljava/nio/ByteBuffer;
lNioBuffer()Ljava/nio/ByteBuffer; @ 6
Event: 16841.448 Thread 0x00007f1f543cf800 Uncommon trap: reason=unreached action
n=reinterpret pc=0x00007f21965db2ec method=java.util.concurrent.locks.AbstractQueuedSynchronizer
euedSynchronizer.doReleaseShared()V @ 69
Event: 43243.574 Thread 0x00007f1f54408800 Uncommon trap: reason=unreached action
n=reinterpret pc=0x00007f21959945c4 method=com.jd.ump.profiler.util.MessagesStor
e$WriteLog2File.run()V @ 22
Event: 43243.574 Thread 0x00007f1f54410800 Uncommon trap: reason=unreached action
n=reinterpret pc=0x00007f21959945c4 method=com.jd.ump.profiler.util.MessagesStor
e$WriteLog2File.run()V @ 22
Event: 43243.575 Thread 0x00007f1f5440f800 Uncommon trap: reason=unreached action
n=reinterpret pc=0x00007f21959945c4 method=com.jd.ump.profiler.util.MessagesStor
e$WriteLog2File.run()V @ 22
Event: 43243.575 Thread 0x00007f1f54418000 Uncommon trap: reason=unreached actio
n=reinterpret pc=0x00007f21959945c4 method=com.jd.ump.profiler.util.MessagesStor
e$WriteLog2File.run()V @ 22

Internal exceptions (10 events):
Event: 42812.465 Thread 0x00007f1f04001000 Exception <a 'java/net/SocketExceptio
n'> (0x000000079fe54f30) thrown at [/HUDSON/workspace/8-2-build-linux-amd64/jdk8
u20/1074/hotspot/src/share/vm/prims/jni.cpp, line 716
Event: 42812.466 Thread 0x00007f1f04001000 Exception <a 'java/net/SocketExceptio
n': Socket closed> (0x000000079fe57398) thrown at [/HUDSON/workspace/8-2-build-l
Linux-amd64/jdk8u20/1074/hotspot/src/share/vm/prims/jni.cpp, line 742
Event: 42813.148 Thread 0x00007f1f04001000 Exception <a 'java/net/SocketExceptio
n'> (0x000000079fe578c0) thrown at [/HUDSON/workspace/8-2-build-linux-amd64/jdk8
u20/1074/hotspot/src/share/vm/prims/jni.cpp, line 716
Event: 42813.148 Thread 0x00007f1f04001000 Exception <a 'java/net/SocketExceptio
n': Socket closed> (0x000000079fe59d28) thrown at [/HUDSON/workspace/8-2-build-l
Linux-amd64/jdk8u20/1074/hotspot/src/share/vm/prims/jni.cpp, line 742
Event: 42821.451 Thread 0x00007f1f7cb62800 Exception <a 'java/net/SocketExceptio
n'> (0x000000079f1a5d90) thrown at [/HUDSON/workspace/8-2-build-linux-amd64/jdk8
u20/1074/hotspot/src/share/vm/prims/jni.cpp, line 716

Detailed Process of Problem Troubleshooting

After the JVM initialization is complete, during the process of class calling and execution, the execution engine will convert bytecode into machine code, which can then be executed in the operating system. In the process of bytecode conversion to machine code, there is also a compilation in the virtual machine, that is, Just-In-Time compilation.

Initially, bytecode in JVM was compiled by the interpreter (Interpreter). When the virtual machine finds that a method or code block is executed frequently, it identifies these codes as hotspot codes.

To improve the execution efficiency of hotspot code, at runtime, the Just-In-Time compiler (JIT) will compile these codes into machine code related to the local platform, perform various levels of optimization, and then save them to memory.

C1 Compiler

The C1 compiler is a simple and fast compiler, with the main focus on local optimization, suitable for programs with short execution times or high startup performance requirements, also known as Client Compiler. For example, GUI applications have certain requirements for the speed of interface startup.

C2 Compiler

The C2 compiler is an optimizer compiler designed for long-running server-side applications, suitable for programs with long execution times or high peak performance requirements, also known as Server Compiler. For example, long-running Java applications on servers have certain requirements for stable operation.

Trigger Standard

In the HotSpot virtual machine, hotspot detection is the trigger standard for JIT.

Hotspot detection is based on counter-based hotspot detection. The virtual machine using this method will establish a counter for each method to count the number of times the method is executed. If the execution count exceeds a certain threshold, it is considered a 'hot method'. The virtual machine prepares two types of counters for each method: method invocation counter (Invocation Counter) and back edge counter (Back Edge Counter). Under the premise of determining the runtime parameters of the virtual machine, both counters have a certain threshold. When the counter exceeds the threshold and overflows, JIT compilation is triggered.

Method call counter

The method call counter is used to count the number of times a method is called, the default threshold is 1500 times under the C1 mode, and 10000 times under the C2 mode. It can be set through -XX: CompileThreshold; while in the layered compilation, the threshold specified by -XX: CompileThreshold will be invalid, and it will be dynamically adjusted according to the current number of methods to be compiled and the number of compilation threads. When the sum of the method call counter and the back edge counter exceeds the method call counter threshold, the JIT compiler will be triggered.

It is obvious that the scheduled task has been executing a certain piece of code all the time, triggering JIT compilation, so JVM performs JIT compilation on this piece of code, but an exception occurred during the compilation process, causing JVM to exit abnormally.

Three, how to solve the problem

Since it is known that the JIT compilation is triggered due to the excessive execution times of hot code, there are two solutions

1: Through JVM command line to perform JIT compilation on a method, the JVM related configuration commands are as follows

java -Xint -version # Interpreter mode, output interpreted mode

java –Xcomp -version # Compilation mode, output compiled mode

java -Xmixed -version # Mixed mode, output mixed mode

-XX:+PrintCompilation (Output JIT compilation information)

-XX:CompileCommand=exclude,the/package/and/Class,methodName # Exclude the specified method from JIT optimization

-XX:CompileCommand='compileonly,java/lang/StringBuffer.*' # Specify methods for compilation

-XX:CompileThreshold=1000 # Through the JIT compiler, the trigger threshold for compiling methods into machine code, which can be understood as the number of times a method is called, for example, calling 1000 times will compile the method into machine code

2: Considering that the program has no problem due to the use of the old version of mysql connection driver, the mysql driver package has been downgraded to restore to a stable version. The problematic version is the mysql driver dependent on spring-boot-2.1.6.RELEASE

Author: Cao Zhi Fei, JD Retail

Source: JD Cloud Developer Community. Please indicate the source of the reprint.