[20190321]smem的显示缺陷.txt
[20190321]smem的显示缺陷.txt
1.smem 加入-m参数显示存在缺陷,map的信息不全:
# smem -tk -m -U oracle -P "oraclepeis|ora_"
Map PIDs AVGPSS PSS
/u01/app/oracle/product/10.2.0/db_1/dbs/ 15 0 0
[vdso] 308 0 0
[vsyscall] 308 0 0
/lib64/libaio.so.1.0.1 308 3.0K 1.1M
/lib64/libnsl-2.12.so 308 7.0K 2.1M
/lib64/ld-2.12.so 308 7.0K 2.1M
/u01/app/oracle/product/10.2.0/db_1/lib/ 308 7.0K 2.1M
/u01/app/oracle/product/10.2.0/db_1/lib/ 308 7.0K 2.1M
/lib64/libdl-2.12.so 308 7.0K 2.1M
/lib64/libnss_files-2.12.so 308 7.0K 2.2M
/lib64/libpthread-2.12.so 308 7.0K 2.2M
/lib64/libm-2.12.so 308 7.0K 2.3M
/lib64/libc-2.12.so 308 12.0K 3.7M
/u01/app/oracle/product/10.2.0/db_1/lib/ 308 14.0K 4.2M
/u01/app/oracle/product/10.2.0/db_1/lib/ 308 21.0K 6.5M
/u01/app/oracle/product/10.2.0/db_1/lib/ 308 21.0K 6.5M
/u01/app/oracle/product/10.2.0/db_1/lib/ 308 32.0K 9.7M
/u01/app/oracle/product/10.2.0/db_1/lib/ 308 56.0K 17.1M
[stack] 308 80.0K 24.1M
/u01/app/oracle/product/10.2.0/db_1/lib/ 308 103.0K 31.2M
/u01/app/oracle/product/10.2.0/db_1/bin/ 308 127.0K 38.3M
<anonymous> 308 242.0K 72.8M
[heap] 308 466.0K 140.5M
/dev/zero 308 561.0K 168.9M
/u01/app/oracle/product/10.2.0/db_1/lib/ 308 589.0K 177.4M
/u01/app/oracle/product/10.2.0/db_1/lib/ 308 1.4M 417.1M
/SYSV94f021f8 308 2.8M 876.1M
-----------------------------------------------------------------
27 8023 6.5M 2.0G
--//Map部分显示宽度不足.可以加宽到80.很容易修改python的脚本,我不懂python,看一下源代码就可以了.
--//修改前注意备份!!
# diff -Nur smem.ORG smem
--- smem.ORG 2019-03-21 11:18:59.117243470 +0800
+++ smem 2013-03-28 11:01:07.000000000 +0800
@@ -330,7 +330,7 @@
pt = maptotals(p)
fields = dict(
- map=('Map', lambda n: n, '%-80.80s', len,
+ map=('Map', lambda n: n, '%-40.40s', len,
'mapping name'),
count=('Count', lambda n: pt[n]['count'], '% 5s', sum,
'number of mappings found'),
# smem.ORG -tk -m -U oracle -P "oraclepeis|ora_"
Map PIDs AVGPSS PSS
/u01/app/oracle/product/10.2.0/db_1/dbs/hc_peis.dat 15 0 0
[vdso] 151 0 0
[vsyscall] 151 0 0
/lib64/libaio.so.1.0.1 151 3.0K 588.0K
/u01/app/oracle/product/10.2.0/db_1/lib/libclsra10.so 151 7.0K 1.1M
/lib64/libnsl-2.12.so 151 7.0K 1.1M
/lib64/libnss_files-2.12.so 151 7.0K 1.1M
/u01/app/oracle/product/10.2.0/db_1/lib/libskgxn2.so 151 7.0K 1.1M
/lib64/libdl-2.12.so 151 7.0K 1.1M
/lib64/ld-2.12.so 151 7.0K 1.1M
/lib64/libpthread-2.12.so 151 7.0K 1.1M
/lib64/libm-2.12.so 151 8.0K 1.2M
/lib64/libc-2.12.so 151 14.0K 2.2M
/u01/app/oracle/product/10.2.0/db_1/lib/libdbcfg10.so 151 15.0K 2.2M
/u01/app/oracle/product/10.2.0/db_1/lib/libocrb10.so 151 22.0K 3.4M
/u01/app/oracle/product/10.2.0/db_1/lib/libskgxp10.so 151 22.0K 3.4M
/u01/app/oracle/product/10.2.0/db_1/lib/libocr10.so 151 34.0K 5.0M
/u01/app/oracle/product/10.2.0/db_1/lib/libocrutl10.so 151 61.0K 9.0M
[stack] 151 97.0K 14.4M
/u01/app/oracle/product/10.2.0/db_1/lib/libhasgen10.so 151 110.0K 16.3M
/u01/app/oracle/product/10.2.0/db_1/bin/oracle 151 222.0K 32.8M
<anonymous> 151 265.0K 39.2M
[heap] 151 488.0K 72.0M
/u01/app/oracle/product/10.2.0/db_1/lib/libnnz10.so 151 640.0K 94.4M
/dev/zero 151 950.0K 140.1M
/u01/app/oracle/product/10.2.0/db_1/lib/libjox10.so 151 1.5M 221.0M
/SYSV94f021f8 151 5.8M 880.7M
---------------------------------------------------------------------------------------------------------
27 3941 10.2M 1.5G
--//PIDS表示查询的进程数量,它是将PSS平均分摊到各个用户.
--//SYSV94f021f8表示共享内存段.
# ipcs -m
------ Shared Memory Segments --------
key shmid owner perms bytes nattch status
0x94f021f8 32768 oracle 640 1176502272 151
--//key=0x94f021f8,不过后面的PSS如果计算的不是很清楚感觉应该是1176502272/1024/1024 = 1122M.难道不过全部加载吗?
--//nattch表示连接使用共享内存段的进程数.正好151可以与smem显示的PIDS对上.不再生产系统折腾,换测试机器测试.
2.测试环境:
# smem -tk -m -U oracle -P "oraclebook|ora_"
Map PIDs AVGPSS PSS
/SYSV00000000 26 0 0
/SYSVe8a8ec10 26 0 0
/u01/app/oracle/product/11.2.0.4/dbhome_1/dbs/hc_book.dat 21 0 0
[vdso] 26 0 0
[vsyscall] 26 0 0
/lib64/libnss_dns-2.5.so 1 24.0K 24.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libnque11.so 6 5.0K 30.0K
/lib64/libresolv-2.5.so 1 35.0K 35.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libclsra11.so 26 4.0K 104.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libocrutl11.so 26 4.0K 104.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libskgxn2.so 26 4.0K 104.0K
/usr/lib64/libaio.so.1.0.1 26 4.0K 104.0K
/usr/lib64/libnuma.so.1 26 4.0K 104.0K
/lib64/libdl-2.5.so 26 8.0K 208.0K
/lib64/libnsl-2.5.so 26 8.0K 208.0K
/lib64/librt-2.5.so 26 8.0K 208.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libdbcfg11.so 26 8.0K 208.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libnfsodm11.so 26 8.0K 208.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libskgxp11.so 26 8.0K 208.0K
/lib64/libnss_files-2.5.so 26 8.0K 212.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libocrb11.so 26 9.0K 234.0K
/lib64/libpthread-2.5.so 26 9.0K 237.0K
/lib64/ld-2.5.so 26 10.0K 260.0K
/lib64/libm-2.5.so 26 12.0K 328.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libocr11.so 26 14.0K 364.0K
/lib64/libc-2.5.so 26 22.0K 581.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libcell11.so 26 69.0K 1.8M
[stack] 26 82.0K 2.1M
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libhasgen11.so 26 162.0K 4.1M
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libnnz11.so 26 231.0K 5.9M
[heap] 26 418.0K 10.6M
/dev/zero 26 793.0K 20.1M
/u01/app/oracle/product/11.2.0.4/dbhome_1/bin/oracle 26 1.3M 35.1M
<anonymous> 26 1.6M 42.4M
---------------------------------------------------------------------------------------------------------
34 809 4.9M 126.1M
--//奇怪在共享内存段使用0.
# ipcs -m
------ Shared Memory Segments --------
key shmid owner perms bytes nattch status
0x00000000 349011969 oracle 640 12582912 26
0x00000000 349044738 oracle 640 633339904 26
0xe8a8ec10 349077507 oracle 640 2097152 26
3.关闭hugepages看看.
vm.nr_hugepages = 0
vm.nr_overcommit_hugepages = 0
# grep -i page /proc/meminfo
AnonPages: 249336 kB
PageTables: 18228 kB
AnonHugePages: 0 kB
HugePages_Total: 0
HugePages_Free: 0
HugePages_Rsvd: 0
HugePages_Surp: 0
Hugepagesize: 2048 kB
# ipcs -m
------ Shared Memory Segments --------
key shmid owner perms bytes nattch status
0x00000000 349208577 oracle 640 12582912 22
0x00000000 349241346 oracle 640 633339904 22
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
0xe8a8ec10 349274115 oracle 640 2097152 22
# smem -tk -m -U oracle -P "oraclebook|ora_"
Map PIDs AVGPSS PSS
/SYSVe8a8ec10 22 0 0
/u01/app/oracle/product/11.2.0.4/dbhome_1/dbs/hc_book.dat 20 0 0
[vdso] 22 0 0
[vsyscall] 22 0 0
/lib64/libnss_dns-2.5.so 1 24.0K 24.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libnque11.so 4 6.0K 24.0K
/lib64/libresolv-2.5.so 1 35.0K 35.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libclsra11.so 22 4.0K 88.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libocrutl11.so 22 4.0K 88.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libskgxn2.so 22 4.0K 88.0K
/usr/lib64/libaio.so.1.0.1 22 4.0K 88.0K
/usr/lib64/libnuma.so.1 22 4.0K 88.0K
/lib64/libdl-2.5.so 22 8.0K 176.0K
/lib64/libnsl-2.5.so 22 8.0K 176.0K
/lib64/librt-2.5.so 22 8.0K 176.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libdbcfg11.so 22 8.0K 176.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libnfsodm11.so 22 8.0K 176.0K
/lib64/libnss_files-2.5.so 22 8.0K 179.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libocrb11.so 22 9.0K 198.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libskgxp11.so 22 9.0K 198.0K
/lib64/libpthread-2.5.so 22 9.0K 200.0K
/lib64/ld-2.5.so 22 10.0K 220.0K
/lib64/libm-2.5.so 22 12.0K 281.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libocr11.so 22 14.0K 308.0K
/lib64/libc-2.5.so 22 22.0K 492.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libcell11.so 22 70.0K 1.5M
[stack] 22 73.0K 1.6M
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libhasgen11.so 22 166.0K 3.6M
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libnnz11.so 22 232.0K 5.0M
[heap] 22 420.0K 9.0M
/dev/zero 22 572.0K 12.3M
/u01/app/oracle/product/11.2.0.4/dbhome_1/bin/oracle 22 1.6M 34.4M
<anonymous> 22 1.8M 38.6M
/SYSV00000000 22 4.0M 88.6M
---------------------------------------------------------------------------------------------------------
34 686 9.1M 198.0M
--///SYSV00000000那行PSS=88.6M.
SYS@book> select /*+ full(A) */ count(*) from sh.sales a;
COUNT(*)
----------
918843
[root@gxqyydg4 IP=100.78 /etc ] # smem -tk -m -U oracle -P "oraclebook|ora_"
Map PIDs AVGPSS PSS
/SYSVe8a8ec10 22 0 0
/u01/app/oracle/product/11.2.0.4/dbhome_1/dbs/hc_book.dat 20 0 0
[vdso] 22 0 0
[vsyscall] 22 0 0
/lib64/libnss_dns-2.5.so 1 24.0K 24.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libnque11.so 4 6.0K 24.0K
/lib64/libresolv-2.5.so 1 35.0K 35.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libclsra11.so 22 4.0K 88.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libocrutl11.so 22 4.0K 88.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libskgxn2.so 22 4.0K 88.0K
/usr/lib64/libaio.so.1.0.1 22 4.0K 88.0K
/usr/lib64/libnuma.so.1 22 4.0K 88.0K
/lib64/libdl-2.5.so 22 8.0K 176.0K
/lib64/libnsl-2.5.so 22 8.0K 176.0K
/lib64/librt-2.5.so 22 8.0K 176.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libdbcfg11.so 22 8.0K 176.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libnfsodm11.so 22 8.0K 176.0K
/lib64/libnss_files-2.5.so 22 8.0K 179.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libocrb11.so 22 9.0K 198.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libskgxp11.so 22 9.0K 198.0K
/lib64/libpthread-2.5.so 22 9.0K 200.0K
/lib64/ld-2.5.so 22 10.0K 220.0K
/lib64/libm-2.5.so 22 12.0K 282.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libocr11.so 22 14.0K 308.0K
/lib64/libc-2.5.so 22 22.0K 492.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libcell11.so 22 70.0K 1.5M
[stack] 22 76.0K 1.6M
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libhasgen11.so 22 166.0K 3.6M
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libnnz11.so 22 232.0K 5.0M
[heap] 22 420.0K 9.0M
/dev/zero 22 642.0K 13.8M
/u01/app/oracle/product/11.2.0.4/dbhome_1/bin/oracle 22 1.6M 35.0M
<anonymous> 22 1.8M 38.7M
/SYSV00000000 24 6.0M 143.7M
---------------------------------------------------------------------------------------------------------
34 747 11.0M 262.4M
--///SYSV00000000那行PSS=143.7M.说明共享内存的分配可以动态变化.
4.关闭hugepages以及设置参数pre_page_sga=true:
# smem -tk -m -U oracle -P "oraclebook|ora_"
Map PIDs AVGPSS PSS
/SYSVe8a8ec10 22 0 0
/u01/app/oracle/product/11.2.0.4/dbhome_1/dbs/hc_book.dat 20 0 0
[vdso] 22 0 0
[vsyscall] 22 0 0
/lib64/libnss_dns-2.5.so 1 24.0K 24.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libnque11.so 4 6.0K 24.0K
/lib64/libresolv-2.5.so 1 35.0K 35.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libclsra11.so 22 4.0K 88.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libocrutl11.so 22 4.0K 88.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libskgxn2.so 22 4.0K 88.0K
/usr/lib64/libaio.so.1.0.1 22 4.0K 88.0K
/usr/lib64/libnuma.so.1 22 4.0K 88.0K
/lib64/libdl-2.5.so 22 8.0K 176.0K
/lib64/libnsl-2.5.so 22 8.0K 176.0K
/lib64/librt-2.5.so 22 8.0K 176.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libdbcfg11.so 22 8.0K 176.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libnfsodm11.so 22 8.0K 176.0K
/lib64/libnss_files-2.5.so 22 8.0K 179.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libocrb11.so 22 9.0K 198.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libskgxp11.so 22 9.0K 198.0K
/lib64/libpthread-2.5.so 22 9.0K 200.0K
/lib64/ld-2.5.so 22 10.0K 220.0K
/lib64/libm-2.5.so 22 12.0K 281.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libocr11.so 22 14.0K 308.0K
/lib64/libc-2.5.so 22 22.0K 492.0K
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libcell11.so 22 70.0K 1.5M
[stack] 22 72.0K 1.5M
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libhasgen11.so 22 166.0K 3.6M
/u01/app/oracle/product/11.2.0.4/dbhome_1/lib/libnnz11.so 22 232.0K 5.0M
[heap] 22 420.0K 9.0M
/dev/zero 22 589.0K 12.7M
/u01/app/oracle/product/11.2.0.4/dbhome_1/bin/oracle 22 1.6M 34.4M
<anonymous> 22 1.8M 38.6M
/SYSV00000000 22 27.8M 611.5M
---------------------------------------------------------------------------------------------------------
34 686 32.8M 721.2M
--//设置pre_page_sga=true,表示启动数据库全部加载整个SGA到内存.
--//633339904/1024/1024 = 604M
--//其实这样后面的PSS内存总和基本表示这个实例使用的内存量.
--//看看官方的定义:
http://docs.oracle.com/cd/E11882_01/server.112/e40402/initparams201.htm#REFRN10174
PRE_PAGE_SGA determines whether Oracle reads the entire SGA into memory at instance startup. Operating system page table
entries are then prebuilt for each page of the SGA. This setting can increase the amount of time necessary for instance
startup, but it is likely to decrease the amount of time necessary for Oracle to reach its full performance capacity
after startup.
--//我看了几台机器,使用hugepages,map对应是共享内存段的都是0,对于这些不熟悉.^_^.
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