LVM Striping

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I am using RHCS cluster(two nodes) for database(oracle 11g). I have mounted data volumes from storage (HP XP 24000). I have done LVM striping. I am using 4 LUNs (each size of 500gb) a total of 2TB. I created LV with I-4 and i-256, as switch parameter. I am suffering from batch processing on my DB server. Some times server get hangged and memory usage become very high. (out of 64gb, oracle uses all the memory) finally turning to server hang. Please suggest.

Affected LV details is as below:=>

[root@MPJBPDCCCB1 ~]# lvdisplay -v /dev/mapper/ccb_vgdata-ccb_lvdata
Using logical volume(s) on command line
--- Logical volume ---
LV Name /dev/ccb_vgdata/ccb_lvdata
VG Name ccb_vgdata
LV UUID AzCy0B-Pjbo-avY7-LeEc-Ymxk-MY8Z-8OrxA0
LV Write Access read/write
LV Status available
# open 1
LV Size 1.95 TB
Current LE 512000
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 4096

Block device 253:85

Striping details for the same LV is as below:=>

ccb_lvdata ccb_vgdata -wi-ao 4 striped 1.95T

Please suggest!

Responses

I am using RHEL5.5 with details "[root@MPJBPDCCCB1 ~]# uname -a
Linux MPJBPDCCCB1 2.6.18-238.12.1.el5 #1 SMP Sat May 7 20:18:50 EDT 2011 x86_64 x86_64 x86_64 GNU/Linux"

Can any body help online !!

Hello Kumar - tuning Red Hat (correctly) for Oracle does not have one approach. There are a number of things you need to consider. Oracle SGA, Hugepages, etc..

I recommend that you search for Tuning RHEL for Oracle. The following is an example that is a bit dated, but may still apply to your environment:
https://access.redhat.com/site/documentation/en-US/Red_Hat_Enterprise_Linux/5/html/Tuning_and_Optimizing_Red_Hat_Enterprise_Linux_for_Oracle_9i_and_10g_Databases/

you will likely need to update
/etc/sysctl.conf
/etc/security/limits.conf
and numerous Oracle DB conf files.

You can watch basic memory usage with free -m, iostat and iotop are good to see what the system is doing. As well as sar -W (to watch swapping)

Be sure that you have configured your storage multipathing correctly also:
(search for HP XP 24000 /etc/multipath.conf)
http://h20565.www2.hp.com/portal/site/hpsc/template.PAGE/public/kb/docDisplay/?sp4ts.oid=3559651&spf_p.tpst=kbDocDisplay&spf_p.prp_kbDocDisplay=wsrp-navigationalState%3DdocId%253Demr_na-c01476873-1%257CdocLocale%253D%257CcalledBy%253D&javax.portlet.begCacheTok=com.vignette.cachetoken&javax.portlet.endCacheTok=com.vignette.cachetoken

Probably a silly question (I'm not seeing it explicitly stated in your posts or followups): when presenting your storage to Oracle, is Oracle consuming that storage as Linux filesystems (i.e., DB files written to EXT3 filesystems on top of the LVs) or is Oracle using ASM to interface with your LVs. If it's the latter, I'd probably skip using LVM for Oracle's storage and just let ASM talk directly to the /dev/sdX devices. Doing so removes some of the abstraction-layers and simplifies any remaining troubleshooting