#!/bin/bash # @Function # Find out the highest cpu consumed threads of java processes, and print the stack of these threads. # # @Usage # $ ./show-busy-java-threads # # @online-doc https://github.com/oldratlee/useful-scripts/blob/dev-2.x/docs/java.md#-show-busy-java-threads # @author Jerry Lee (oldratlee at gmail dot com) # @author superhj1987 (superhj1987 at 126 dot com) # # NOTE about Bash Traps and Pitfalls: # # 1. DO NOT combine var declaration and assignment which value supplied by subshell! # for example: readonly var1=$(echo value1) # local var1=$(echo value1) # # declaration make exit code of assignment to be always 0, # aka. the exit code of command in subshell is discarded. # tested on bash 3.2.57/4.2.46 # NOTE: DO NOT declare var PROG as readonly, because its value is supplied by subshell. PROG="$(basename "$0")" readonly PROG_VERSION='2.5.0-dev' # choosing between $0 and BASH_SOURCE # https://stackoverflow.com/a/35006505/922688 # How can I get the source directory of a Bash script from within the script itself? # https://stackoverflow.com/questions/59895 # Will $0 always include the path to the script? # https://unix.stackexchange.com/questions/119929 readonly -a COMMAND_LINE=("${BASH_SOURCE[0]}" "$@") # Get current user name via whoami command # See https://www.lifewire.com/current-linux-user-whoami-command-3867579 # Because if run command by `sudo -u`, env var $USER is not rewritten/correct, just inherited from outside! # # NOTE: DO NOT declare var USER as readonly, because its value is supplied by subshell. USER="$(whoami)" ################################################################################ # util functions ################################################################################ # NOTE: $'foo' is the escape sequence syntax of bash readonly ec=$'\033' # escape char readonly eend=$'\033[0m' # escape end readonly nl=$'\n' # new line colorEcho() { local color=$1 shift # if stdout is console, turn on color output. [ -t 1 ] && echo "${ec}[1;${color}m$*$eend" || echo "$@" } colorPrint() { local color=$1 shift colorEcho "$color" "$@" [[ -n "$append_file" && -w "$append_file" ]] && echo "$@" >>"$append_file" [[ -n "$store_dir" && -w "$store_dir" ]] && echo "$@" >>"${store_file_prefix}$PROG" } # shellcheck disable=SC2120 normalPrint() { echo "$@" [[ -n "$append_file" && -w "$append_file" ]] && echo "$@" >>"$append_file" [[ -n "$store_dir" && -w "$store_dir" ]] && echo "$@" >>"${store_file_prefix}$PROG" } redPrint() { colorPrint 31 "$@" } greenPrint() { colorPrint 32 "$@" } yellowPrint() { colorPrint 33 "$@" } bluePrint() { colorPrint 36 "$@" } die() { redPrint "Error: $*" 1>&2 exit 1 } logAndRun() { echo "$@" echo "$@" } logAndCat() { echo "$@" echo cat } # Bash RegEx to check floating point numbers from user input # https://stackoverflow.com/questions/13790763 isNonNegativeFloatNumber() { [[ "$1" =~ ^[+]?[0-9]+\.?[0-9]*$ ]] } isNaturalNumber() { [[ "$1" =~ ^[+]?[0-9]+$ ]] } isNaturalNumberList() { [[ "$1" =~ ^([0-9]+)(,[0-9]+)*$ ]] } # print calling(quoted) command line which is able to copy and paste to rerun safely # # How to get the complete calling command of a BASH script from inside the script (not just the arguments) # https://stackoverflow.com/questions/36625593 printCallingCommandLine() { local arg isFirst=true for arg in "${COMMAND_LINE[@]}"; do if $isFirst; then isFirst=false else printf ' ' fi printf '%q' "$arg" done echo } usage() { local -r exit_code="${1:-0}" (($# > 0)) && shift # shellcheck disable=SC2015 [ "$exit_code" != 0 ] && local -r out=/dev/stderr || local -r out=/dev/stdout (($# > 0)) && colorEcho 31 "$*$nl" >$out cat >$out <<EOF Usage: ${PROG} [OPTION]... [delay [count]] Find out the highest cpu consumed threads of java processes, and print the stack of these threads. Example: ${PROG} # show busy java threads info ${PROG} 1 # update every 1 second, (stop by eg: CTRL+C) ${PROG} 3 10 # update every 3 seconds, update 10 times Output control: -p, --pid <java pid(s)> find out the highest cpu consumed threads from the specified java process. support pid list(eg: 42,47). default from all java process. -c, --count <num> set the thread count to show, default is 5. set count 0 to show all threads. -a, --append-file <file> specifies the file to append output as log. -S, --store-dir <dir> specifies the directory for storing the intermediate files, and keep files. default store intermediate files at tmp dir, and auto remove after run. use this option to keep files so as to review jstack/top/ps output later. delay the delay between updates in seconds. count the number of updates. delay/count arguments imitates the style of vmstat command. jstack control: -s, --jstack-path <path> specifies the path of jstack command. -F, --force set jstack to force a thread dump. use when jstack does not respond (process is hung). -m, --mix-native-frames set jstack to print both java and native frames (mixed mode). -l, --lock-info set jstack with long listing. prints additional information about locks. CPU usage calculation control: -i, --cpu-sample-interval specifies the delay between cpu samples to get thread cpu usage percentage during this interval. default is 0.5 (second). set interval 0 to get the percentage of time spent running during the *entire lifetime* of a process. Miscellaneous: -h, --help display this help and exit. -V, --version display version information and exit. EOF exit "$exit_code" } progVersion() { echo "$PROG $PROG_VERSION" exit } ################################################################################ # Check os support ################################################################################ uname | grep '^Linux' -q || die "$PROG only support Linux, not support $(uname) yet!" ################################################################################ # parse options ################################################################################ # NOTE: ARGS can not be declared as readonly!! # readonly declaration make exit code of assignment to be always 0, aka. the exit code of `getopt` in subshell is discarded. # tested on bash 4.2.46 ARGS=$( getopt -n "$PROG" -a -o c:p:a:s:S:i:Pd:FmlhV \ -l count:,pid:,append-file:,jstack-path:,store-dir:,cpu-sample-interval:,use-ps,top-delay:,force,mix-native-frames,lock-info,help,version \ -- "$@" ) || { echo usage 1 } eval set -- "${ARGS}" count=5 cpu_sample_interval=0.5 while true; do case "$1" in -c | --count) count="$2" shift 2 ;; -p | --pid) pid_list="$2" shift 2 ;; -a | --append-file) append_file="$2" shift 2 ;; -s | --jstack-path) jstack_path="$2" shift 2 ;; -S | --store-dir) store_dir="$2" shift 2 ;; # support the option name -P,--use-ps for compatibility -P | --use-ps) cpu_sample_interval=0 shift ;; # support the option name -d,--top-delay for compatibility -i | --cpu-sample-interval | -d | --top-delay) cpu_sample_interval="$2" shift 2 ;; -F | --force) force=-F shift ;; -m | --mix-native-frames) mix_native_frames=-m shift ;; -l | --lock-info) more_lock_info=-l shift ;; -h | --help) usage ;; -V | --version) progVersion ;; --) shift break ;; esac done update_delay=${1:-0} isNonNegativeFloatNumber "$update_delay" || die "update delay($update_delay) is not a non-negative float number!" [ -z "$1" ] && update_count=1 || update_count=${2:-0} isNaturalNumber "$update_count" || die "update count($update_count) is not a natural number!" if [ -n "$pid_list" ]; then pid_list="${pid_list//[[:space:]]/}" # delete white space isNaturalNumberList "$pid_list" || die "pid(s)($pid_list) is illegal! example: 42 or 42,99,67" fi # check the directory of append-file(-a) mode, create if not exist. if [ -n "$append_file" ]; then if [ -e "$append_file" ]; then [ -f "$append_file" ] || die "$append_file(specified by option -a, for storing run output files) exists but is not a file!" [ -w "$append_file" ] || die "file $append_file(specified by option -a, for storing run output files) exists but is not writable!" else append_file_dir="$(dirname "$append_file")" if [ -e "$append_file_dir" ]; then [ -d "$append_file_dir" ] || die "directory $append_file_dir(specified by option -a, for storing run output files) exists but is not a directory!" [ -w "$append_file_dir" ] || die "directory $append_file_dir(specified by option -a, for storing run output files) exists but is not writable!" else mkdir -p "$append_file_dir" || die "fail to create directory $append_file_dir(specified by option -a, for storing run output files)!" fi fi fi # check store directory(-S) mode, create directory if not exist. if [ -n "$store_dir" ]; then if [ -e "$store_dir" ]; then [ -d "$store_dir" ] || die "$store_dir(specified by option -S, for storing output files) exists but is not a directory!" [ -w "$store_dir" ] || die "directory $store_dir(specified by option -S, for storing output files) exists but is not writable!" else mkdir -p "$store_dir" || die "fail to create directory $store_dir(specified by option -S, for storing output files)!" fi fi isNonNegativeFloatNumber "$cpu_sample_interval" || die "cpu sample interval($cpu_sample_interval) is not a non-negative float number!" ################################################################################ # search/check the existence of jstack command # # search order/priority: # 1. from -s option # 2. from under env var JAVA_HOME # 3. from under env var PATH ################################################################################ if [ -n "$jstack_path" ]; then # 1. check jstack_path set by -s option [ -f "$jstack_path" ] || die "$jstack_path (set by -s option) is NOT found!" [ -x "$jstack_path" ] || die "$jstack_path (set by -s option) is NOT executable!" elif [ -n "$JAVA_HOME" ]; then # 2. search jstack under JAVA_HOME if [ -f "$JAVA_HOME/bin/jstack" ]; then [ -x "$JAVA_HOME/bin/jstack" ] || die "found \$JAVA_HOME/bin/jstack($JAVA_HOME/bin/jstack) is NOT executable!${nl}Use -s option set jstack path manually." jstack_path="$JAVA_HOME/bin/jstack" elif [ -f "$JAVA_HOME/../bin/jstack" ]; then [ -x "$JAVA_HOME/../bin/jstack" ] || die "found \$JAVA_HOME/../bin/jstack($JAVA_HOME/../bin/jstack) is NOT executable!${nl}Use -s option set jstack path manually." jstack_path="$JAVA_HOME/../bin/jstack" fi elif command -v jstack &>/dev/null; then # 3. search jstack under PATH jstack_path="$(command -v jstack)" [ -x "$jstack_path" ] || die "found $jstack_path from PATH is NOT executable!${nl}Use -s option set jstack path manually." else die "jstack NOT found by JAVA_HOME(${JAVA_HOME:-not set}) setting and PATH!${nl}Use -s option set jstack path manually." fi ################################################################################ # biz logic ################################################################################ # NOTE: DO NOT declare var run_timestamp as readonly, because its value is supplied by subshell. run_timestamp="$(date "+%Y-%m-%d_%H:%M:%S.%N")" readonly uuid="${PROG}_${run_timestamp}_${$}_${RANDOM}" readonly tmp_store_dir="/tmp/${uuid}" if [ -n "$store_dir" ]; then readonly store_file_prefix="$store_dir/${run_timestamp}_" else readonly store_file_prefix="$tmp_store_dir/${run_timestamp}_" fi mkdir -p "$tmp_store_dir" cleanupWhenExit() { rm -rf "$tmp_store_dir" &>/dev/null } trap cleanupWhenExit EXIT headInfo() { colorEcho "0;34;42" ================================================================================ echo "$(date "+%Y-%m-%d %H:%M:%S.%N") [$((update_round_num + 1))/$update_count]: $(printCallingCommandLine)" colorEcho "0;34;42" ================================================================================ echo } if [ -n "${pid_list}" ]; then readonly ps_process_select_options="-p $pid_list" else readonly ps_process_select_options="-C java -C jsvc" fi __die_when_no_java_process_found() { if [ -n "${pid_list}" ]; then die "process($pid_list) is not running, or not java process!" else die 'No java process found!' fi } # output field: pid, thread id(lwp), pcpu, user # order by pcpu(percentage of cpu usage) # # NOTE: # use ps command to find busy thread(cpu usage) # cpu usage of ps command is expressed as # the percentage of time spent running during the *entire lifetime* of a process, # this is not ideal in general. findBusyJavaThreadsByPs() { # 1. sort by %cpu by ps option `--sort -pcpu` # unfortunately, ps from `procps-ng 3.3.12`, `--sort` does not work properly with other options, # use # ps <other options> # combined # sort -k3,3nr # instead of # ps <other options> --sort -pcpu # 2. use wide output(unlimited width) by ps option `-ww` # avoid trunk user column to username_fo+ or $uid alike # shellcheck disable=SC2206 local -a ps_cmd_line=(ps $ps_process_select_options -wwLo 'pid,lwp,pcpu,user' --no-headers) # DO NOT combine var ps_out declaration and assignment, because its value is supplied by subshell. local ps_out ps_out="$("${ps_cmd_line[@]}" | sort -k3,3nr)" [ -n "$ps_out" ] || __die_when_no_java_process_found if [ -n "$store_dir" ]; then echo "$ps_out" | logAndCat "${ps_cmd_line[@]} | sort -k3,3nr" >"${store_file_prefix}$((update_round_num + 1))_ps" fi if ((count > 0)); then echo "$ps_out" | head -n "${count}" else echo "$ps_out" fi } # top with output field: thread id, %cpu __top_threadId_cpu() { # DO NOT combine var java_pid_list declaration and assignment, because its value is supplied by subshell. local java_pid_list # shellcheck disable=SC2086 java_pid_list="$(ps $ps_process_select_options -o pid --no-headers)" [ -n "$java_pid_list" ] || __die_when_no_java_process_found # shellcheck disable=SC2086 java_pid_list="$(echo $java_pid_list | tr ' ' ,)" # join with , # 1. sort by %cpu by top option `-o %CPU` # unfortunately, top version 3.2 does not support -o option(supports from top version 3.3+), # use # HOME="$tmp_store_dir" top -H -b -n 1 # combined # sort # instead of # HOME="$tmp_store_dir" top -H -b -n 1 -o '%CPU' # 2. change HOME env var when run top, # so as to prevent top command output format being change by .toprc user config file unexpectedly # 3. use option `-d 0.5`(update interval 0.5 second) and `-n 2`(update 2 times), # and use second time update data to get cpu percentage of thread in 0.5 second interval # 4. top v3.3, there is 1 black line between 2 update; # but top v3.2, there is 2 blank lines between 2 update! local -a top_cmd_line=(top -H -b -d "$cpu_sample_interval" -n 2 -p "$java_pid_list") # DO NOT combine var ps_out declaration and assignment, because its value is supplied by subshell. local top_out top_out=$(HOME="$tmp_store_dir" "${top_cmd_line[@]}") if [ -n "$store_dir" ]; then echo "$top_out" | logAndCat "${top_cmd_line[@]}" >"${store_file_prefix}$((update_round_num + 1))_top" fi # DO NOT combine var result_threads_top_info declaration and assignment, because its value is supplied by subshell. local result_threads_top_info result_threads_top_info=$( echo "$top_out" | awk '{ # from text line to empty line, increase block index if (previousLine && !$0) blockIndex++ # only print 4th text block(blockIndex == 3), aka. process info of second top update if (blockIndex == 3 && $1 ~ /^[0-9]+$/) print $1, $9 # $1 is thread id field, $9 is %cpu field previousLine = $0 }' ) [ -n "$result_threads_top_info" ] || __die_when_no_java_process_found echo "$result_threads_top_info" | sort -k2,2nr } __complete_pid_user_by_ps() { # ps output field: pid, thread id(lwp), user # shellcheck disable=SC2206 local -a ps_cmd_line=(ps $ps_process_select_options -wwLo 'pid,lwp,user' --no-headers) # DO NOT combine var ps_out declaration and assignment, because its value is supplied by subshell. local ps_out ps_out="$("${ps_cmd_line[@]}")" if [ -n "$store_dir" ]; then echo "$ps_out" | logAndCat "${ps_cmd_line[@]}" >"${store_file_prefix}$((update_round_num + 1))_ps" fi local idx=0 threadId pcpu output_fields while read -r threadId pcpu; do ((count <= 0 || idx < count)) || break # output field: pid, threadId, pcpu, user output_fields="$(echo "$ps_out" | awk -v "threadId=$threadId" -v "pcpu=$pcpu" '$2==threadId { print $1, threadId, pcpu, $3; exit }')" if [ -n "$output_fields" ]; then ((idx++)) echo "$output_fields" fi done } # output format is same as function findBusyJavaThreadsByPs findBusyJavaThreadsByTop() { __top_threadId_cpu | __complete_pid_user_by_ps } printStackOfThreads() { local idx=0 pid threadId pcpu user threadId0x while read -r pid threadId pcpu user; do threadId0x="0x$(printf %x "${threadId}")" ((idx++)) local jstackFile="${store_file_prefix}$((update_round_num + 1))_jstack_${pid}" [ -f "${jstackFile}" ] || { # shellcheck disable=SC2206 local -a jstack_cmd_line=("$jstack_path" ${force} $mix_native_frames $more_lock_info ${pid}) if [ "${user}" == "${USER}" ]; then # run without sudo, when java process user is current user logAndRun "${jstack_cmd_line[@]}" >"${jstackFile}" elif [ $UID == 0 ]; then # if java process user is not current user, must run jstack with sudo logAndRun sudo -u "${user}" "${jstack_cmd_line[@]}" >"${jstackFile}" else # current user is not root user, so can not run with sudo; print error message and rerun suggestion redPrint "[$idx] Fail to jstack busy(${pcpu}%) thread(${threadId}/${threadId0x}) stack of java process(${pid}) under user(${user})." redPrint "User of java process($user) is not current user($USER), need sudo to rerun:" yellowPrint " sudo $(printCallingCommandLine)" normalPrint continue fi || { redPrint "[$idx] Fail to jstack busy(${pcpu}%) thread(${threadId}/${threadId0x}) stack of java process(${pid}) under user(${user})." normalPrint rm "${jstackFile}" &>/dev/null continue } } bluePrint "[$idx] Busy(${pcpu}%) thread(${threadId}/${threadId0x}) stack of java process(${pid}) under user(${user}):" if [ -n "$mix_native_frames" ]; then local sed_script="/--------------- $threadId ---------------/,/^---------------/ { /--------------- $threadId ---------------/b # skip first separator line /^---------------/d # delete second separator line p }" elif [ -n "$force" ]; then local sed_script="/^Thread ${threadId}:/,/^$/ { /^$/d; p # delete end separator line }" else local sed_script="/ nid=${threadId0x} /,/^$/ { /^$/d; p # delete end separator line }" fi { sed "$sed_script" -n "${jstackFile}" echo } | tee ${append_file:+-a "$append_file"} ${store_dir:+-a "${store_file_prefix}$PROG"} done } ################################################################################ # Main ################################################################################ main() { local update_round_num # if update_count <= 0, infinite loop till user interrupted (eg: CTRL+C) for ((update_round_num = 0; update_count <= 0 || update_round_num < update_count; ++update_round_num)); do ((update_round_num > 0)) && sleep "$update_delay" [[ -n "$append_file" || -n "$store_dir" ]] && headInfo | tee ${append_file:+-a "$append_file"} ${store_dir:+-a "${store_file_prefix}$PROG"} >/dev/null ((update_count != 1)) && headInfo if [ "$cpu_sample_interval" == 0 ]; then findBusyJavaThreadsByPs else findBusyJavaThreadsByTop fi | printStackOfThreads done } main
Usage:
show-busy-java-threads #Find out the most CPU consuming thread (5 by default) from all running Java processes and print out its thread stack #By default, it will automatically find the most CPU consuming thread from all Java processes, which is more convenient to use #Of course, you can manually specify the Java process Id to be analyzed through the - p option to ensure that only the information of the Java process you care about will be displayed Show busy Java threads - P < specified java process ID > show-busy-java-threads -p 42 show-busy-java-threads -p 42,47 Show busy Java threads - C < number of thread stacks to show > Show busy Java threads < seconds between repeated executions > [< times of repeated executions >] #Multiple execution; The use of these two parameters is similar to the vmstat command Show busy Java threads - a < run output recorded files > #Record to file for retrospective review Show busy Java threads - s < directory where jstack output files are stored > #Specify the storage directory of jstack output files to facilitate subsequent analysis of records ############################## #Note: ############################## #If the user of the Java process is different from the current user executing the script, jstack cannot the Java process #In order to switch to the user of Java process, sudo needs to be added for execution, which can solve the following problems: sudo show-busy-java-threads Show busy Java threads - s < specify the full path of the jstack command > #For sudo mode operation, Java_ The home environment variable cannot be passed to root, #The root user often does not configure JAVA_HOME is not easy to configure, and the jstack command cannot be found. #In this case, it is more convenient to explicitly specify the path of the jstack command #- m option: add the - m option when executing the jstack command to display the Native stack frame, which is not required for general application troubleshooting show-busy-java-threads -m #- F option: add the - F option when executing the jstack command (if there is no response from the direct jstack, it is used to force jstack). Generally, it is not necessary to use it show-busy-java-threads -F #- l option: add the - l option when executing the jstack command to display more lock related information. Generally, it is not necessary to use it #Note: when used with the - m -F option, it may greatly increase the time consumption of jstack operation show-busy-java-threads -l #Help information $ show-busy-java-threads -h Usage: show-busy-java-threads [OPTION]... [delay [count]] Find out the highest cpu consumed threads of java processes, and print the stack of these threads. Example: show-busy-java-threads # show busy java threads info show-busy-java-threads 1 # update every 1 second, (stop by eg: CTRL+C) show-busy-java-threads 3 10 # update every 3 seconds, update 10 times Output control: -p, --pid <java pid(s)> find out the highest cpu consumed threads from the specified java process. support pid list(eg: 42,47). default from all java process. -c, --count <num> set the thread count to show, default is 5. set count 0 to show all threads. -a, --append-file <file> specifies the file to append output as log. -S, --store-dir <dir> specifies the directory for storing the intermediate files, and keep files. default store intermediate files at tmp dir, and auto remove after run. use this option to keep files so as to review jstack/top/ps output later. delay the delay between updates in seconds. count the number of updates. delay/count arguments imitates the style of vmstat command. jstack control: -s, --jstack-path <path> specifies the path of jstack command. -F, --force set jstack to force a thread dump. use when jstack does not respond (process is hung). -m, --mix-native-frames set jstack to print both java and native frames (mixed mode). -l, --lock-info set jstack with long listing. prints additional information about locks. CPU usage calculation control: -i, --cpu-sample-interval specifies the delay between cpu samples to get thread cpu usage percentage during this interval. default is 0.5 (second). set interval 0 to get the percentage of time spent running during the *entire lifetime* of a process. Miscellaneous: -h, --help display this help and exit. -V, --version display version information and exit.
Example
$ show-busy-java-threads [1] Busy(57.0%) thread(23355/0x5b3b) stack of java process(23269) under user(admin): "pool-1-thread-1" prio=10 tid=0x000000005b5c5000 nid=0x5b3b runnable [0x000000004062c000] java.lang.Thread.State: RUNNABLE at java.text.DateFormat.format(DateFormat.java:316) at com.xxx.foo.services.common.DateFormatUtil.format(DateFormatUtil.java:41) at com.xxx.foo.shared.monitor.schedule.AppMonitorDataAvgScheduler.run(AppMonitorDataAvgScheduler.java:127) at com.xxx.foo.services.common.utils.AliTimer$2.run(AliTimer.java:128) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) at java.lang.Thread.run(Thread.java:662) [2] Busy(26.1%) thread(24018/0x5dd2) stack of java process(23269) under user(admin): "pool-1-thread-2" prio=10 tid=0x000000005a968800 nid=0x5dd2 runnable [0x00000000420e9000] java.lang.Thread.State: RUNNABLE at java.util.Arrays.copyOf(Arrays.java:2882) at java.lang.AbstractStringBuilder.expandCapacity(AbstractStringBuilder.java:100) at java.lang.AbstractStringBuilder.append(AbstractStringBuilder.java:572) at java.lang.StringBuffer.append(StringBuffer.java:320) - locked <0x00000007908d0030> (a java.lang.StringBuffer) at java.text.SimpleDateFormat.format(SimpleDateFormat.java:890) at java.text.SimpleDateFormat.format(SimpleDateFormat.java:869) at java.text.DateFormat.format(DateFormat.java:316) at com.xxx.foo.services.common.DateFormatUtil.format(DateFormatUtil.java:41) at com.xxx.foo.shared.monitor.schedule.AppMonitorDataAvgScheduler.run(AppMonitorDataAvgScheduler.java:126) at com.xxx.foo.services.common.utils.AliTimer$2.run(AliTimer.java:128) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) at java.lang.Thread.run(Thread.java:662) ......