一、问题描述
某次某云主机访问异常，登录云主机后来发现vnc界面夯死，输入命令无反应，console界面发送重启指令也无反应，只能云平台管理页面强制重启。
二、问题分析：
1>重启后查看syslog日志发现，系统故障时间前后大量出现如下报错：
Linux中，默认日志服务为rsyslog，系统内核和许多程序会产生各种错误信息、警告信息和其他的提示信息都会写入到syslog日志中。
……
kernel: WARNING: [write_iter] inode ifops has restore
systemd-journald: Forwarding to syslog missed 1 messages
……
systemd: [email protected]: Service has no hold-off time, scheduling restart.
systemd: Stopped Getty on tty1.
systemd: Started Getty on tty1.
kernel: WARNING: [write_iter] inode ifops has restore
再往前查看：
Jun 6 21:33:13 video-stream kernel: stream_convert invoked oom-killer: gfp_mask=0x24280ca, order=0, oom_score_adj=0
Jun 6 21:33:13 video-stream systemd-journald: Forwarding to syslog missed 6 messages.
Jun 6 21:33:13 video-stream kernel: stream_convert cpuset=4ebca70fe5bffef91f0e4d355ecceca3b977acdf70f519a9a7ffbc02f38c0613 mems_allowed=0
Jun 6 21:33:13 video-stream kernel: CPU: 7 PID: 11545 Comm: stream_convert Tainted: G OE 4.4.0-150-generic #176-Ubuntu
Jun 6 21:33:13 video-stream kernel: Hardware name: Fedora Project OpenStack Nova, BIOS seabios-1.7.5-11.el7 04/01/2014
Jun 6 21:33:13 video-stream kernel: 0000000000000286 bc6e93ac5afb4302 ffff8804999cfad0 ffffffff8140b481
Jun 6 21:33:13 video-stream kernel: ffff8804999cfc88 ffff8801d9366200 ffff8804999cfb40 ffffffff8121888e
Jun 6 21:33:13 video-stream kernel: 0000000000000000 ffff880814d62c00 ffff88081351aa00 ffff8804999cfb28
Jun 6 21:33:13 video-stream kernel: Call Trace:
Jun 6 21:33:13 video-stream kernel: [<ffffffff8140b481>] dump_stack+0x63/0x82
Jun 6 21:33:13 video-stream kernel: [<ffffffff8121888e>] dump_header+0x5a/0x1c3
Jun 6 21:33:13 video-stream kernel: [<ffffffff813a2814>] ? apparmor_capable+0xc4/0x1b0
Jun 6 21:33:13 video-stream kernel: [<ffffffff8119c80b>] oom_kill_process+0x20b/0x3d0
Jun 6 21:33:13 video-stream kernel: [<ffffffff8119cc39>] out_of_memory+0x219/0x460
Jun 6 21:33:13 video-stream kernel: [<ffffffff811a2c53>] __alloc_pages_slowpath.constprop.88+0x943/0xaf0
Jun 6 21:33:13 video-stream kernel: [<ffffffff811a3088>] __alloc_pages_nodemask+0x288/0x2a0
Jun 6 21:33:13 video-stream kernel: [<ffffffff8185ebdd>] ? __schedule+0x30d/0x810
Jun 6 21:33:13 video-stream kernel: [<ffffffff811f00aa>] alloc_pages_vma+0xaa/0x270
Jun 6 21:33:13 video-stream kernel: [<ffffffff811ccba9>] handle_mm_fault+0x1439/0x1b80
Jun 6 21:33:13 video-stream kernel: [<ffffffff81419c24>] ? call_rwsem_down_read_failed+0x14/0x30
Jun 6 21:33:13 video-stream kernel: [<ffffffff8106ddf4>] __do_page_fault+0x1a4/0x410
Jun 6 21:33:13 video-stream kernel: [<ffffffff8106e0c7>] trace_do_page_fault+0x37/0xe0
Jun 6 21:33:13 video-stream kernel: [<ffffffff810660a9>] do_async_page_fault+0x19/0x70
Jun 6 21:33:13 video-stream kernel: [<ffffffff81866698>] async_page_fault+0x28/0x30
Jun 6 21:33:13 video-stream kernel: Mem-Info:
Jun 6 21:33:13 video-stream kernel: active_anon:7909729 inactive_anon:28750 isolated_anon:0#012 active_file:10180 inactive_file:9878 isolated_file:474#012 unevictable:1021 dirty:0 writeback:168 unstable:0#012 slab_reclaimable:124746 slab_unreclaimable:16959#012 mapped:8098 shmem:85614 pagetables:23340 bounce:0#012 free:52373 free_pcp:43 free_cma:0
Jun 6 21:33:13 video-stream kernel: Node 0 DMA free:15872kB min:32kB low:40kB high:48kB active_anon:0kB inactive_anon:0kB active_file:0kB inactive_file:0kB unevictable:0kB isolated(anon):0kB isolated(file):0kB present:15992kB managed:15904kB mlocked:0kB dirty:0kB writeback:0kB mapped:0kB shmem:0kB slab_reclaimable:0kB slab_unreclaimable:32kB kernel_stack:0kB pagetables:0kB unstable:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB writeback_tmp:0kB pages_scanned:0 all_unreclaimable? yes
Jun 6 21:33:13 video-stream kernel: lowmem_reserve[]: 0 2935 32117 32117 32117
Jun 6 21:33:13 video-stream kernel: Node 0 DMA32 free:132392kB min:6172kB low:7712kB high:9256kB active_anon:2708808kB inactive_anon:4456kB active_file:3692kB inactive_file:3632kB unevictable:880kB isolated(anon):0kB isolated(file):444kB present:3129212kB managed:3048336kB mlocked:880kB dirty:0kB writeback:0kB mapped:1952kB shmem:15860kB slab_reclaimable:130572kB slab_unreclaimable:7676kB kernel_stack:5328kB pagetables:7840kB unstable:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB writeback_tmp:0kB pages_scanned:48596 all_unreclaimable? yes
Jun 6 21:33:13 video-stream kernel: lowmem_reserve[]: 0 0 29182 29182 29182
Jun 6 21:33:14 video-stream kernel: Node 0 Normal free:61228kB min:61376kB low:76720kB high:92064kB active_anon:28930108kB inactive_anon:110544kB active_file:37028kB inactive_file:35880kB unevictable:3204kB isolated(anon):0kB isolated(file):1452kB present:30408704kB managed:29882528kB mlocked:3204kB dirty:0kB writeback:672kB mapped:30440kB shmem:326596kB slab_reclaimable:368412kB slab_unreclaimable:60128kB kernel_stack:7264kB pagetables:85520kB unstable:0kB bounce:0kB free_pcp:172kB local_pcp:0kB free_cma:0kB writeback_tmp:0kB pages_scanned:528168 all_unreclaimable? yes
Jun 6 21:33:14 video-stream kernel: lowmem_reserve[]: 0 0 0 0 0
Jun 6 21:33:14 video-stream kernel: Node 0 DMA: 0*4kB 0*8kB 0*16kB 0*32kB 2*64kB (U) 1*128kB (U) 1*256kB (U) 0*512kB 1*1024kB (U) 1*2048kB (M) 3*4096kB (M) = 15872kB
Jun 6 21:33:14 video-stream kernel: Node 0 DMA32: 2563*4kB (UMEH) 9038*8kB (UMEH) 3117*16kB (UMEH) 0*32kB 0*64kB 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 132428kB
Jun 6 21:33:14 video-stream kernel: Node 0 Normal: 9485*4kB (UMEH) 2433*8kB (UMEH) 228*16kB (UMEH) 0*32kB 0*64kB 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 61052kB
Jun 6 21:33:14 video-stream kernel: Node 0 hugepages_total=0 hugepages_free=0 hugepages_surp=0 hugepages_size=1048576kB
Jun 6 21:33:14 video-stream kernel: Node 0 hugepages_total=0 hugepages_free=0 hugepages_surp=0 hugepages_size=2048kB
Jun 6 21:33:14 video-stream kernel: 106579 total pagecache pages
Jun 6 21:33:14 video-stream kernel: 0 pages in swap cache
Jun 6 21:33:14 video-stream kernel: Swap cache stats: add 0, delete 0, find 0/0
Jun 6 21:33:14 video-stream kernel: Free swap = 0kB
Jun 6 21:33:14 video-stream kernel: Total swap = 0kB
Jun 6 21:33:14 video-stream kernel: 8388477 pages RAM
Jun 6 21:33:14 video-stream kernel: 0 pages HighMem/MovableOnly
Jun 6 21:33:14 video-stream kernel: 151785 pages reserved
Jun 6 21:33:14 video-stream kernel: 0 pages cma reserved
Jun 6 21:33:14 video-stream kernel: 0 pages hwpoisoned
Jun 6 21:33:14 video-stream kernel: [ pid ] uid tgid total_vm rss nr_ptes nr_pmds swapents oom_score_adj name
Jun 6 21:33:14 video-stream kernel: [ 999] 0 999 20193 9334 41 3 0 0 systemd-journal
Jun 6 21:33:14 video-stream kernel: [ 1047] 0 1047 173206 297 34 4 0 0 lvmetad
Jun 6 21:33:14 video-stream kernel: [ 1071] 0 1071 11363 857 24 3 0 -1000 systemd-udevd
Jun 6 21:33:14 video-stream kernel: [ 1119] 100 1119 25081 199 19 3 0 0 systemd-timesyn
Jun 6 21:33:14 video-stream kernel: [ 1725] 0 1725 4032 215 12 3 0 0 dhclient
Jun 6 21:33:14 video-stream kernel: [ 1839] 0 1839 7156 278 18 3 0 0 systemd-logind
Jun 6 21:33:14 video-stream kernel: [ 1841] 108 1841 10755 317 27 3 0 -900 dbus-daemon
Jun 6 21:33:14 video-stream kernel: [ 1851] 0 1851 6511 377 20 3 0 0 atd
Jun 6 21:33:14 video-stream kernel: [ 1854] 0 1854 130412 906 72 3 0 0 NetworkManager
Jun 6 21:33:14 video-stream kernel: [ 1863] 0 1863 6932 493 18 3 0 0 cron
un 6 21:33:14 video-stream kernel: [ 1867] 0 1867 58693 43 17 3 0 0 lxcfs
Jun 6 21:33:14 video-stream kernel: [ 1881] 0 1881 1099 292 8 3 0 0 acpid
Jun 6 21:33:14 video-stream kernel: [ 1885] 0 1885 138114 8659 135 4 0 0 rsyslogd
Jun 6 21:33:14 video-stream kernel: [ 1897] 0 1897 34398 2016 36 3 0 0 python
Jun 6 21:33:14 video-stream kernel: [ 1912] 0 1912 3343 50 11 3 0 0 mdadm
Jun 6 21:33:14 video-stream kernel: [ 1976] 1001 1976 179237 629 19 4 0 0 node_exporter
Jun 6 21:33:14 video-stream kernel: [ 1982] 0 1982 43333 2450 51 3 0 0 unattended-upgr
Jun 6 21:33:14 video-stream kernel: [ 1994] 0 1994 253929 5042 82 5 0 0 containerd
Jun 6 21:33:14 video-stream kernel: [ 2020] 0 2020 16378 532 36 3 0 -1000 sshd
Jun 6 21:33:14 video-stream kernel: [ 2028] 0 2028 69883 497 38 4 0 0 polkitd
Jun 6 21:33:14 video-stream kernel: [ 2044] 0 2044 4033 619 13 3 0 0 dhclient
Jun 6 21:33:14 video-stream kernel: [ 2072] 65534 2072 12896 485 29 3 0 0 dnsmasq
Jun 6 21:33:14 video-stream kernel: [ 2230] 0 2230 1305 29 9 3 0 0 iscsid
Jun 6 21:33:14 video-stream kernel: [ 2231] 0 2231 1430 882 9 3 0 -17 iscsid
Jun 6 21:33:14 video-stream kernel: [ 2299] 0 2299 3618 395 12 3 0 0 agetty
Jun 6 21:33:14 video-stream kernel: [ 2760] 0 2760 1111 405 8 3 0 -1000 watchdog
Jun 6 21:33:14 video-stream kernel: [ 3337] 0 3337 5884 49 17 3 0 0 rpc.idmapd
Jun 6 21:33:14 video-stream kernel: [ 3342] 0 3342 10862 892 26 3 0 0 rpc.mountd
Jun 6 21:33:14 video-stream kernel: [ 3404] 0 3404 11906 363 27 3 0 0 rpcbind
Jun 6 21:33:14 video-stream kernel: [ 3624] 0 3624 301432 9623 115 5 0 -500 dockerd
Jun 6 21:33:14 video-stream kernel: [ 7875] 0 7875 27277 193 11 4 0 -999 containerd-shim
Jun 6 21:33:14 video-stream kernel: [ 7892] 0 7892 1438 106 8 3 0 0 bash
Jun 6 21:33:14 video-stream kernel: [ 7929] 0 7929 1471 175 6 3 0 0 bash
Jun 6 21:33:14 video-stream kernel: [ 2502] 0 2502 27277 253 10 4 0 -999 containerd-shim
Jun 6 21:33:14 video-stream kernel: [ 2517] 0 2517 1126 17 8 3 0 0 sh
Jun 6 21:33:14 video-stream kernel: [ 2533] 0 2533 5369355814 758099 2247 254 0 0 RapidStor
Jun 6 21:33:14 video-stream kernel: [ 2672] 0 2672 26925 191 9 4 0 -999 containerd-shim
Jun 6 21:33:14 video-stream kernel: [ 2689] 0 2689 1126 18 8 3 0 0 sh
Jun 6 21:33:14 video-stream kernel: [ 2703] 0 2703 5369645817 1040585 3051 255 0 0 RapidStor
Jun 6 21:33:14 video-stream kernel: [19425] 0 19425 1471 180 6 3 0 0 bash
Jun 6 21:33:14 video-stream kernel: [29971] 0 29971 26925 197 10 4 0 -999 containerd-shim
Jun 6 21:33:14 video-stream kernel: [29986] 0 29986 1126 17 8 3 0 0 sh
Jun 6 21:33:14 video-stream kernel: [30002] 0 30002 5369769857 6006959 16123 276 0 0 stream_convert
Jun 6 21:33:14 video-stream kernel: [22234] 0 22234 466558 9673 145 5 0 0 sdatad
Jun 6 21:33:14 video-stream kernel: [22267] 0 22267 1365401 1165 266 8 0 0 srepd
Jun 6 21:33:14 video-stream kernel: [22440] 0 22440 185308 1148 97 4 0 0 rpcserver
Jun 6 21:33:14 video-stream kernel: [22466] 0 22466 249034 436 45 4 0 0 sdatalogd
Jun 6 21:33:14 video-stream kernel: [22478] 0 22478 161010 389 74 3 0 0 I2Availability
Jun 6 21:33:14 video-stream kernel: [22480] 0 22480 22818 50 15 3 0 0 i2monitor
Jun 6 21:33:14 video-stream kernel: [22483] 0 22483 51541 399 63 4 0 0 HaDetector
Jun 6 21:33:14 video-stream kernel: [22498] 0 22498 41655 514 55 3 0 0 collector
Jun 6 21:33:14 video-stream kernel: [22500] 0 22500 41951 377 56 3 0 0 TapeMgr
Jun 6 21:33:14 video-stream kernel: [27820] 0 27820 3664 352 11 3 0 0 agetty
Jun 6 21:33:14 video-stream kernel: Out of memory: Kill process 30002 (stream_convert) score 731 or sacrifice child
Jun 6 21:33:14 video-stream kernel: Killed process 30002 (stream_convert) total-vm:21479079428kB, anon-rss:24027836kB, file-rss:0kB
Jun 6 21:33:17 video-stream containerd: time="2022-06-06T21:33:17.535433701+08:00" level=info msg="shim reaped" id=4ebca70fe5bffef91f0e4d355ecceca3b977acdf70f519a9a7ffbc02f38c0613
Jun 6 21:33:17 video-stream dockerd: time="2022-06-06T21:33:17.620768383+08:00" level=info msg="ignoring event" module=libcontainerd namespace=moby topic=/tasks/delete type="*events.TaskDelete"
Jun 6 21:33:19 video-stream containerd: time="2022-06-06T21:33:19.234553076+08:00" level=info msg="shim containerd-shim started" address="/containerd-shim/moby/4ebca70fe5bffef91f0e4d355ecceca3b977acdf70f519a9a7ffbc02f38c0613/shim.sock" debug=false pid=11835
Jun 6 21:33:21 video-stream kernel: WARNING: [write_iter] inode ifops has restore.
Jun 6 21:33:21 video-stream kernel: WARNING: [write_iter] inode ifops has restore.
Jun 6 21:33:31 video-stream kernel: WARNING: [write_iter] inode ifops has restore.
Jun 6 21:33:41 video-stream kernel: WARNING: [write_iter] inode ifops has restore.
Jun 6 21:33:51 video-stream kernel: WARNING: [write_iter] inode ifops has restore.
从上述日志可看到有OOM报错及相关内存错误，之后便开始大量出现[write_iter] inode ifops has restore。OOM发送在大量使用swap之后，会kill掉内存占用最大的进程。这是操作系统系统自身的一种保护机制，以防更多的进程不能正常工作。
一个进程的异常终止，通常有两种情况，一种是crash，另一种是被kill掉了。crash是指程序出现了自己无法解决的异常情况，只能终止。
kill -l #查看系统所有的信号
信号 值 处理动作 发出信号的原因
----------------------------------------------------------------------
SIGHUP 1 A 终端挂起或者控制进程终止
SIGINT 2 A 键盘中断（如break键被按下）
SIGQUIT 3 C 键盘的退出键被按下
SIGILL 4 C 非法指令
SIGABRT 6 C 由abort(3)发出的退出指令
SIGFPE 8 C 浮点异常
SIGKILL 9 AEF Kill信号
SIGSEGV 11 C 无效的内存引用
SIGPIPE 13 A 管道破裂: 写一个没有读端口的管道
SIGALRM 14 A 由alarm(2)发出的信号
SIGTERM 15 A 终止信号
SIGUSR1 30,10,16 A 用户自定义信号1
SIGUSR2 31,12,17 A 用户自定义信号2
SIGCHLD 20,17,18 B 子进程结束信号
SIGCONT 19,18,25 进程继续（曾被停止的进程）
SIGSTOP 17,19,23 DEF 终止进程
SIGTSTP 18,20,24 D 控制终端（tty）上按下停止键
SIGTTIN 21,21,26 D 后台进程企图从控制终端读
SIGTTOU 22,22,27 D 后台进程企图从控制终端写
#信号动作说明
A 缺省的动作是终止进程
B 缺省的动作是忽略此信号
C 缺省的动作是终止进程并进行内核映像转储（dump core）
D 缺省的动作是停止进程
E 信号不能被捕获
F 信号不能被忽略
strace -T -tt -e trace=all -p pid #来跟踪分析程序
一般机器僵死，通常是Kernel出现了死锁，而Kernel不会知道自己死锁了，所以也不会在屏幕上显示相关信息。这时，可尝试使用Kernel的Debug工具来对vmcore进行分析，可以参考如下文章:http://people.redhat.com/anderson/crash_whitepaper/；另外可参看pstore 实现自动“抓捕”内核崩溃日志来分析。
2>查看上次重启时间
last | grep reboot #输出如下，上次重启为4月份
reboot system boot 4.4.0-150-generi Wed Jun 8 10:10 still running
reboot system boot 4.4.0-150-generi Wed Apr 6 20:21 still running
reboot system boot 4.4.0-150-generi Tue Mar 29 17:46 still running
reboot system boot 4.4.0-150-generi Tue Oct 26 20:44 still running
reboot system boot 4.4.0-150-generi Mon Oct 26 19:38 still running
last reboot | head -1 #查看最近一条Linux操作系统重启记录
last -x|grep shutdown | head -1 #查看上一次关机日期和时间，但可能并不能找出系统Linux操作系统非正常关机的情形
last -F |grep carsh #查看上一次宕机记录
3> 内核core信息查看
程序异常退出时，内核会生成一个core文件（内存映像以及一些调试信息）；可以通过使用gdb来查看core文件，从而知道指示出导致程序出错的代码所在的文件和行数。我们可利用coredump技术追查进程崩溃原因
ulimit -c #查看core文件的生成开关，若结果为0，则便是关闭了此功能，不会生成core文件
ulimit -c unlimited #标识此core文件的大小不受限制，程序异常宕的是啥会生产一个core文件
ulimit -c filesize #指定filesize，如果生成的信息超过此大小，将会被裁剪，最终生成一个不完整的core文件，在调试此core文件时，gdb会提示错误
ulimit -c 1024 #设置core文件的大小为1024K，只在当前shell下生效，永久生效在/etc下profile文件末尾加 ulimit -c 1024
#全局生效
vi /root/.bash_profile #加入ulitmit -S -c unlimited
source /root/.bash_profile
cat /proc/sys/kernel/core_uses_pid
echo "1" > /proc/sys/kernel/core_uses_pid
echo "/var/corefile/core-%e-%p-%t" > core_pattern #将core文件统一生成到/var/corefile目录,以下为参数说明：
%p - insert pid into filename 添加pid
%u - insert current uid into filename 添加当前uid
%g - insert current gid into filename 添加当前gid
%s - insert signal that caused the coredump into the filename 添加导致产生core的 信号
%t - insert UNIX time that the coredump occurred into filename 添加core文件生成 的unix时间
%h - insert hostname where the coredump happened into filename 添加主机名
%e - insert coredumping executable name into filename 添加命令名
echo "./dump-%t-%e-%s-%p-%g-%u" > /proc/sys/kernel/core_pattern
#core文件查看
gdb -core=core.xxxx
file ./a.out
bt
#或通过gdb 程序名 core文件名，然后通过bt或者where查看程序崩溃时的堆栈信息
gdb test core.8482
#启用打开core dump，默认不开启；core dump文件的默认位置与可执行程序在同一目录下
vi ~/.bash_profile #加入ulimit -S -c unlimited > /dev/null 2>&1
vi /etc/security/limits.conf #增加
* soft core 0 #对所有用户打开core dump
user soft core 0或@group soft core 0 #只对某些用户或用户组打开core dump
#ulimit -S -c 0 > /dev/null 2>&1 #注释掉
#core dump文件名的模式保存在/proc/sys/kernel/core_pattern中，缺省值是core；以更改core dump文件的位置
echo "/tmp/cores/core" > /proc/sys/kernel/core_pattern #更改位置到/tmp/cores下
在stack trace的信息里，可借助nm、addr2line分析，查看函数地址的指令，用法如下
nm -C [appName] | grep [functionName]
nm -C [libName] | grep [functionName]
#查看异常所在的代码行数：
addr2line -e [appName] [address]
addr2line -e [libName] [address]
#反汇编出现死机的内核模块
objdump -D -l raid456.ko > /home/md.txt #查看/home/md.txt 并查找raid5d_second函数的地址，定位到如下带有<>符号的位置
000000000000bae0 <raid5d_second>: ##前面的地址即该函数的地址
注意：/proc/sys/kernel/core_uses_pid可以控制core文件的文件名是否添加PID作为扩展，如果值为0，表示未启用，生成的core文件统一命名为core，否则生成的core文件格式为core.XXXX；
4>通过dmesg(display message)命令显示内核环形缓冲区的消息，从而可查看进程崩溃的相关信，主要有：
在内核中列出所有加载的驱动程序
列出所有检测到的设备
在操作级别获得大量系统信息，如系统架构、CPU、安装的硬件、ram等
显示开机信息，系统在引导过程中的各种事件信息；kernel 会将开机信息存储在 ring buffer 中
运行dmesg时，它会显示大量信息。dmesg的输出通常配合less或grep查看；执行：dmesg -c 清除dmesg缓冲区日志
dmesg -d -T |grep -i Memory #便于阅读的方式显示日志日期和时间
dmesg -l warn #查看指定级别日志,有：
emerg - 系统无法使用
alert - 操作必须立即执行
crit - 紧急条件
err - 错误条件
warn - 警告条件
notice - 正常但重要的条件
info - 信息
debug - 调试级别的消息
5>检查message日志
/var/log/messages该日志文件是许多进程日志文件的汇总，系统启动后的信息和错误日志， 它是linux的公共日志文件，记录Linux内核消息及各种应用程序的公共日志信息，包括启动、IO错误、网络错误、程序故障等。对于未使用独立日志文件的应用程序或服务，一般都可以从该文件获得相关的事件记录信息。
综上，本次Linux系统僵死可能还是出现在内核层面，且跟应用程序的内存有关。
附录
也可以借助如Webalizer、Awstats（图形化）等专用日志分析工具来分析。