solaris修改shminfo_shmmax参数无效解决

环境介绍：双机操作系统：solaris10数据库版本：oracle11gR164bit当前主机的主机名称和IP：fly-db2192.168.20.21当前备机的主机名称和IP：fly-db1192.168.20.20

环境介绍：

双机 操作系统：solaris 10 数据库版本：oracle 11g R1 64bit 当前主机的主机名称和IP：fly-db2 192.168.20.21 当前备机的主机名称和IP：fly-db1 192.168.20.20

背景：

主备机的物理内存均为94G，近期对备机的物理内存扩容一倍，并修改了数据库层面的相关内存参数，以及主备机的操作系统参数shmsys:shminfo_shmmax，注意是主备的shmsys:shminfo_shmmax参数均已修改，详情请查看下面链接的博文

今晚对fly-db1主机（目前的备机)的物理内存扩容一倍后，重启操作系统，因主备机的shmsys:shminfo_shmmax参数均已经修改，重启操作系统后，理论上该参数设置生效，通过双机软件将数据库从fly-db2切换到fly-db1，切换失败，在双机软件中，查看到out of memory错误，在数据库alert日志，查看到如下报错：

WARNING: The system does not seem to be configured optimally. Creating a segment of size 0x0000000220000000 failed. Please change the shm parameters so that a segment can be created for this size. While this is not a fatal issue, creating one segment may improve performance 如果手工启动，则报错如下： SQL> startup ORA-27102: out of memory SVR4 Error: 22: Invalid argument bash-3.00$ oerr ora 27102 27102, 00000, "out of memory" // *Cause: Out of memory // *Action: Consult the trace file for details

从以上报错分析，因为使用的是同一个数据库，操作系统层面只修改了shmsys:shminfo_shmmax参数,定位为当前备机fly-db1该参数设置未生效

1、对比主备机的/etc/system文件，是一致的

bash-3.00#hostname fly-db1 bash-3.00# diff /etc/system /home/oracle/system_flydb2_131220.bak

2、百度之solaris out of memory,查看到以下blog，文章中涉及/etc/project文件，我们可以这么理解/etc/project文件，如果/etc/system和/etc/project中设置了相同的参数，则操作系统会忽略/etc/system的设置，而采用/etc/project的设置，/etc/project文件可以针对特定用户设置只对自己生效的参数
https://blogs.oracle.com/mandalika/entry/oracle_on_solaris_10_fixing Oracle on Solaris 10 : Fixing the 'ORA-27102: out of memory' Error

3、查看到当前备机fly-db1主机的/etc/project中设置了max-shm-memory的最大大小为60G，即最大的共享内存段为60G，如下所示：

bash-3.00# hostname fly-db1 bash-3.00# cat /etc/project system:0:::: user.root:1:::: noproject:2:::: default:3::::project.max-shm-memory=(privileged,64424509440,deny) group.staff:10:::: bash-3.00# bc scale=5 64424509440/1024/1024/1024 60.00000

4、查看当前主机（fly-db2）的/etc/project内容，未设置max-shm-memory的最大值，，所以在该操作系统，生效的是/etc/system的设置

bash-3.00#hostname fly-db2 bash-3.00# cat /etc/project system:0:::: user.root:1:::: noproject:2:::: default:3:::: group.staff:10::::

5、将当前备机fly-db1的/etc/project修改成和当前主机的/etc/project一样

bash-3.00#hostname fly-db1 bash-3.00# cat /etc/project system:0:::: user.root:1:::: noproject:2:::: default:3:::: group.staff:10::::

6、重启操作系统

bash-3.00# sync bash-3.00# sync bash-3.00# sync bash-3.00# shutdown -i6 -g0 -y

7、双机切换，成功切换到备机fly-db1

以下内容来自： https://blogs.oracle.com/mandalika/entry/oracle_on_solaris_10_fixing Symptom: As part of a database tuning effort you increase the SGA/PGA sizes; and Oracle greets with an ORA-27102: out of memory error message. The system had enough free memory to serve the needs of Oracle. SQL> startup ORA-27102: out of memory SVR4 Error: 22: Invalid argument Diagnosis $ oerr ORA 27102 27102, 00000, "out of memory" // \*Cause: Out of memory // \*Action: Consult the trace file for details Not so helpful. Let's look the alert log for some clues. % tail -2 alert.log WARNING: EINVAL creating segment of size 0x000000028a006000 fix shm parameters in /etc/system or equivalent Oracle is trying to create a 10G shared memory segment (depends on SGA/PGA sizes), but operating system (Solaris in this example) responded with an invalid argument (EINVAL) error message. There is a little hint about setting shm parameters in /etc/system. Prior to Solaris 10, shmsys:shminfo_shmmax parameter has to be set in /etc/system with maximum memory segment value that can be created. 8M is the default value on Solaris 9 and prior versions; where as 1/4th of the physical memory is the default on Solaris 10 and later. On a Solaris 10 (or later) system, it can be verified as shown below: % prtconf | grep Mem Memory size: 32760 Megabytes % id -p uid=59008(oracle) gid=10001(dba) projid=3(default) % prctl -n project.max-shm-memory -i project 3 project: 3: default NAME PRIVILEGE VALUE FLAG ACTION RECIPIENT project.max-shm-memory privileged 7.84GB - deny - system 16.0EB max deny - Now it is clear that the system is using the default value of 8G in this scenario, where as the application (Oracle) is trying to create a memory segment (10G) larger than 8G. Hence the failure.So, the solution is to configure the system with a value large enough for the shared segment being created, so Oracle succeeds in starting up the database instance. On Solaris 9 and prior releases, it can be done by adding the following line to /etc/system, followed by a reboot for the system to pick up the new value. set shminfo_shmmax = 0x000000028a006000 However shminfo_shmmax parameter was obsoleted with the release of Solaris 10; and Sun doesn't recommend setting this parameter in /etc/system even though it works as expected. On Solaris 10 and later, this value can be changed dynamically on a per project basis with the help of resource control facilities . This is how we do it on Solaris 10 and later: % prctl -n project.max-shm-memory -r -v 10G -i project 3 % prctl -n project.max-shm-memory -i project 3 project: 3: default NAME PRIVILEGE VALUE FLAG ACTION RECIPIENT project.max-shm-memory privileged 10.0GB - deny - system 16.0EB max deny - Note that changes made with the prctl command on a running system are temporary, and will be lost when the system is rebooted. To make the changes permanent, create a project with projadd command and associate it with the user account as shown below: % projadd -p 3 -c 'eBS benchmark' -U oracle -G dba -K 'project.max-shm-memory=(privileged,10G,deny)' OASB % usermod -K project=OASB oracle Finally make sure the project is created with projects -l or cat /etc/project commands. % projects -l ... ... OASB projid : 3 comment: "eBS benchmark" users : oracle groups : dba attribs: project.max-shm-memory=(privileged,10737418240,deny) % cat /etc/project ... ... OASB:3:eBS benchmark:oracle:dba:project.max-shm-memory=(privileged,10737418240,deny) With these changes, Oracle would start the database up normally. SQL> startup ORACLE instance started. Total System Global Area 1.0905E+10 bytes Fixed Size 1316080 bytes Variable Size 4429966096 bytes Database Buffers 6442450944 bytes Redo Buffers 31457280 bytes Database mounted. Database opened.

本文出自 “斜阳悠悠寸草心” 博客，请务必保留此出处