记一次生产数据库系统内存使用过高的案例

727次阅读  |  发布于4年以前

根据监控平台信息,发现数据库平台节点2内存使用率过高,达到98%。通过查询占用内存较高的进程、检查TFA状态、同步TFA配置等方式,使得系统恢复正常运作。

概述

根据监控平台信息,发现某数据库平台节点2内存使用率过高,内存使用率达到98%。

1. 查询占用内存较高的进程

grid     280483 183124  0 18:21 ?        00:00:00 [asmcmd daemon]
grid     280493 155171  0 18:21 ?        00:00:00 [asmcmd daemon]
grid     280497 104733  0 18:21 ?        00:00:00 [asmcmd daemon]
grid     280499 187375  0 18:21 ?        00:00:00 [asmcmd daemon]
grid     280533 239249  0 18:21 ?        00:00:00 [asmcmd daemon]
grid     280534 157752  0 18:21 ?        00:00:00 [asmcmd daemon]
grid     280536 281960  0 18:21 ?        00:00:00 [asmcmd daemon]
grid     280545  69656  0 18:21 ?        00:00:00 [asmcmd daemon]
grid     280552 128541  0 18:21 ?        00:00:00 [asmcmd daemon]
grid     280553  63409  0 18:21 ?        00:00:00 [asmcmd daemon]
grid     280558 108705  0 18:21 ?        00:00:00 [asmcmd daemon]
grid     280575 194378  0 18:21 ?        00:00:00 [asmcmd daemon]

内存使用率暂用最高的为asmcmd daemon,这个进程究竟在做什么导致消耗这么高的内存呢?

记下来跟踪一下该进程过程。

wait4(163639, [{WIFEXITED(s) && WEXITSTATUS(s) == 0}], 0, NULL) = 163639
open("/tmp/clsecho_stderr_file.txt", O_RDONLY) = 4
ioctl(4, SNDCTL_TMR_TIMEBASE or SNDRV_TIMER_IOCTL_NEXT_DEVICE or TCGETS, 0x7ffc8333d180) = -1 ENOTTY (Inappropriate ioctl for device)
lseek(4, 0, SEEK_CUR)                   = 0
fstat(4, {st_mode=S_IFREG|0644, st_size=285, ...}) = 0
fcntl(4, F_SETFD, FD_CLOEXEC)           = 0
read(4, "Can't open '/oracle/app/12.2.0/g"..., 8192) = 285
stat("/oracle/app/12.2.0/grid/bin/clsecho", {st_mode=S_IFREG|0755, st_size=11405, ...}) = 0
geteuid()                               = 1001
geteuid()                               = 1001
getegid()                               = 501
lseek(4, 99, SEEK_SET)                  = 99
lseek(4, 0, SEEK_CUR)                   = 99
pipe([6, 7])                            = 0
pipe([8, 9])                            = 0
clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0x7f059005ea10) = 164739
close(9)                                = 0
close(7)                                = 0
read(8, "", 4)                          = 0
close(8)                                = 0
ioctl(6, SNDCTL_TMR_TIMEBASE or SNDRV_TIMER_IOCTL_NEXT_DEVICE or TCGETS, 0x7ffc8333d0f0) = -1 ENOTTY (Inappropriate ioctl for device)
lseek(6, 0, SEEK_CUR)                   = -1 ESPIPE (Illegal seek)
fstat(6, {st_mode=S_IFIFO|0600, st_size=0, ...}) = 0
brk(0)                                  = 0x81493d000
brk(0x81495e000)                        = 0x81495e000
read(6, "20-Jul-20 18:14 ASMCMD Backgroun"..., 8192) = 102
read(6, "", 8192)                       = 0
--- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=164739, si_status=0, si_utime=0, si_stime=195} ---
fstat(6, {st_mode=S_IFIFO|0600, st_size=0, ...}) = 0
close(6)                                = 0
brk(0)                                  = 0x81495e000
brk(0)                                  = 0x81495e000
brk(0x81495c000)                        = 0x81495c000
brk(0)                                  = 0x81495c000
wait4(164739, [{WIFEXITED(s) && WEXITSTATUS(s) == 0}], 0, NULL) = 164739
close(4)                                = 0
open("/tmp/clsecho_stderr_file.txt", O_RDONLY) = 4
ioctl(4, SNDCTL_TMR_TIMEBASE or SNDRV_TIMER_IOCTL_NEXT_DEVICE or TCGETS, 0x7ffc8333d180) = -1 ENOTTY (Inappropriate ioctl for device)
lseek(4, 0, SEEK_CUR)                   = 0
fstat(4, {st_mode=S_IFREG|0644, st_size=285, ...}) = 0
fcntl(4, F_SETFD, FD_CLOEXEC)           = 0
read(4, "Can't open '/oracle/app/12.2.0/g"..., 8192) = 285
stat("/oracle/app/12.2.0/grid/bin/clsecho", {st_mode=S_IFREG|0755, st_size=11405, ...}) = 0
geteuid()                               = 1001
geteuid()                               = 1001
getegid()                               = 501
lseek(4, 99, SEEK_SET)                  = 99
lseek(4, 0, SEEK_CUR)                   = 99
pipe([6, 7])                            = 0
pipe([8, 9])                            = 0
clone(^CProcess 219522 detached

在这些进程上进行strace跟踪发现,无法连接到ASM实例以及对套接字文件不存在等大量无效调用。

"ASMCMD Background (PID = 118768):  Invalid file handle for pipe /tmp/asmcmd_fg_118436" 2> /tmp/clsecho_stderr_file.txt

进一步的分析/tmp/clsecho_stderr_file.txt发现,但随着CPU的增加,这些进程正在系统地从系统中获取更多交换空间。

[root@ tmp]# more clsecho_stderr_file.txt
Can't open '/oracle/app/12.2.0/grid/log/diag/asmcmd/user_grid/xxssd2/alert/alert.log' for append
CLSU-00100: operating system function: open failed failed with error data: 2
CLSU-00101: operating system error message: No such file or directory
CLSU-00103: error location: SlfFopen1

这就很巧了该目录为TFA的诊断目录。说明当前TFA存在问题

2. 检查TFA状态

[grid@~]$ tfactlTFA-00104 Cannot establish connection with TFA Server. Please check TFA Certificates

果然,节点2存在问题,连不上TFA 服务,那么节点1呢?因为节点1此时没有发生内存使用过高情况。

节点1TFA情况:

.------------------------------------------------------------------------------------.
|                                      xxssd1                                      |
+-----------------------------------------------------------------------+------------+
| Configuration Parameter                                               | Value      |
+-----------------------------------------------------------------------+------------+
| TFA Version                                                           | 19.2.1.0.0 |
| Java Version                                                          | 1.8        |
| Public IP Network                                                     | true       |
| Automatic Diagnostic Collection                                       | true       |
| Alert Log Scan                                                        | true       |
| Disk Usage Monitor                                                    | true       |
| Managelogs Auto Purge                                                 | false      |
| Trimming of files during diagcollection                               | true       |
| Inventory Trace level                                                 | 1          |
| Collection Trace level                                                | 1          |
| Scan Trace level                                                      | 1          |
| Other Trace level                                                     | 1          |
| Granular Tracing                                                      | false      |
| Debug Mask (Hex)                                                      | 0          |
| Repository current size (MB)                                          | 6908       |
| Repository maximum size (MB)                                          | 10240      |
| Max Size of TFA Log (MB)                                              | 50         |
| Max Number of TFA Logs                                                | 10         |
| Max Size of Core File (MB)                                            | 50         |
| Max Collection Size of Core Files (MB)                                | 500        |
| Max File Collection Size (MB)                                         | 5120       |
| Minimum Free Space to enable Alert Log Scan (MB)                      | 500        |
| Time interval between consecutive Disk Usage Snapshot(minutes)        | 60         |
| Time interval between consecutive Managelogs Auto Purge(minutes)      | 60         |
| Logs older than the time period will be auto purged(days[d]|hours[h]) | 30d        |
| Automatic Purging                                                     | true       |
| Age of Purging Collections (Hours)                                    | 12         |
| TFA IPS Pool Size                                                     | 5          |
| TFA ISA Purge Age (seconds)                                           | 604800     |
| TFA ISA Purge Mode                                                    | profile    |
| TFA ISA Purge Thread Delay (minutes)                                  | 60         |
| Setting for ACR redaction (none|SANITIZE|MASK)                        | none       |
| Email Notification will be sent for CHA EVENTS if address is set      | false      |
| AUTO Collection will be generated for CHA EVENTS                      | false      |

tfactl> status

.-----------------------------------------------------------------------------------------------.
| Host     | Status of TFA | PID  | Port | Version    | Build ID             | Inventory Status |
+----------+---------------+------+------+------------+----------------------+------------------+
| xxssd1   | RUNNING       | 8075 | 5000 | 19.2.1.0.0 | 19210020190425110550 | COMPLETE         |
| xxssd2   | NOT RUNNING   | -    |      |            |                      |                  |
'----------+---------------+------+------+------------+----------------------+------------------'

节点1运行正常,节点2没有运行,多次手动启动没有反应,报错如下:

Unable to determine the status of TFA in other nodes.

说明TFA 节点互联状态已经失效了。

3. 同步TFA配置

如果另一个节点TFA存在问题,那么可以在正常节点进行同步配置。

WARNING - TFA Software is older than 180 days. Please consider upgrading TFA to the latest version.


Current Node List in TFA :
1. xxssd1
2. xxssd2

Node List in Cluster :
1. xxssd1
2. xxssd2

Node List to sync TFA Certificates :
     1  xxssd2

Do you want to update this node list? [Y|N] [N]:

Syncing TFA Certificates on xxssd2 :

TFA_HOME on xxssd2 : /oracle/app/12.2.0/grid/tfa/xxssd2/tfa_home

Please Enter the password for xxssd2 :

Is password same for all the nodes? [Y|N] [Y]: Y

Shutting down TFA on xxssd2...
Copying TFA Certificates to xxssd2...
Copying SSL Properties to xxssd2...
Shutting down TFA on xxssd2...
Sleeping for 5 seconds...
Starting TFA on xxssd2...

WARNING - TFA Software is older than 180 days. Please consider upgrading TFA to the latest version.

.-------------------------------------------------------------------------------------------------.
| Host     | Status of TFA | PID    | Port | Version    | Build ID             | Inventory Status |
+----------+---------------+--------+------+------------+----------------------+------------------+
| xxssd1   | RUNNING       |   8075 | 5000 | 19.2.1.0.0 | 19210020190425110550 | COMPLETE         |
| xxssd2   | RUNNING       | 230525 | 5000 | 19.2.1.0.0 | 19210020190425110550 | COMPLETE         |
'----------+---------------+--------+------+------------+----------------------+------------------'

4. 后续处理

TFA配置完成后,内存的使用率就开下降,内存释放。

             total        used        free      shared  buff/cache   available
Mem:           1007         942          16           5          49          54
Swap:            31           0          31
[root@xxssd2 ~]# free -g
              total        used        free      shared  buff/cache   available
Mem:           1007         907          50           5          49          89
Swap:            31           0          31
[root@xxssd2 ~]# free -g
              total        used        free      shared  buff/cache   available
Mem:           1007         827         131           5          48         169
Swap:            31           0          31
[root@xxssd2 ~]# free -g
              total        used        free      shared  buff/cache   available
Mem:           1007         820         137           5          48         176
Swap:            31           0          31
[root@xxssd2 ~]# free -g
              total        used        free      shared  buff/cache   available
Mem:           1007         745         213           5          48         251
Swap:            31           0          31
[root@xxssd2 ~]# free -g
              total        used        free      shared  buff/cache   available
Mem:           1007         745         213           5          48         251
Swap:            31           0          31
[root@xxssd2 ~]# free -g
              total        used        free      shared  buff/cache   available
Mem:           1007         745         213           5          48         251
Swap:            31           0          31
[root@xxssd2 ~]# free -g
              total        used        free      shared  buff/cache   available
Mem:           1007         745         213           5          48         251
Swap:            31           0          31
[root@xxssd2 ~]# free -g
              total        used        free      shared  buff/cache   available
Mem:           1007         745         213           5          48         251
Swap:            31           0          31
[root@xxssd2 ~]# free -g
              total        used        free      shared  buff/cache   available
Mem:           1007         745         213           5          48         251
Swap:            31           0          31

5. 总结

TFA(Trace File Analyzer Collector)是个11.2版本上推出的用来收集Grid Infrastructure/RAC环境下的诊断日志的工具,它可以用非常简单的命令协助用户收集RAC里的日志,以便进一步进行诊断;TFA是类似diagcollection的一个oracle 集群日志收集器,而且TFA比diagcollection集中和自动化的诊断信息收集能力更强大。

建议生产环境数据库均关闭TFA自动收集、分析功能(Autodiagcollect)从而避免类似情况发生影响生产环境数据库的正常运行。

.------------------------------------------------------------------------------------.
|                                      gatzyca1                                      |
+-----------------------------------------------------------------------+------------+
| Configuration Parameter                                               | Value      |
+-----------------------------------------------------------------------+------------+
| TFA Version                                                           | 19.2.1.0.0 |
| Java Version                                                          | 1.8        |
| Public IP Network                                                     | true       |
| Automatic Diagnostic Collection                                       | true       |

注:关闭自动收集、分析功能不影响数据库正常运行,不影响TFA的日志收集、整合以及打包功能。

root用户执行:

tfactl set autodiagcollect = OFF

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