Re: Solved: Exacheck reports "FAIL Storage Server Check Exadata Smart Flash Cache should be actually used"

  • From: Svetoslav Gyurov <softice@xxxxxxxxx>
  • To: dmarc-noreply@xxxxxxxxxxxxx
  • Date: Tue, 17 Nov 2015 15:47:56 +0000

Yong, Oracle released a similar note today:
Oracle Data Files should not be placed on the +RECO ASM diskgroup (Doc ID
2074156.1)

If you upgrade from ESS less than 11.2.3.2.0 the cachingPolicy for RECO
diskgroup will be changed from default to none but should be kept default
for DATA.

On Tue, Nov 17, 2015 at 3:34 PM, Yong Huang <dmarc-noreply@xxxxxxxxxxxxx>
wrote:

Three weeks ago I reported the titled problem. It was later found that the
grid disk caching policy was set to 'none'. After changing it to 'default'
caching policy, caching statistics started to show non-zero values:

CellCLI> alter griddisk DATA_CD_00_dmp2cel03 cachingPolicy="default";
GridDisk DATA_CD_00_dmp2cel03 successfully altered

CellCLI> list griddisk DATA_CD_00_dmp2cel03 detail
...
cachingPolicy: default
...

CellCLI> list metriccurrent fc_by_used
FC_BY_USED FLASHCACHE 6,690 MB

On the compute node:

SQL> select * from gv$sysstat where name like '%cache%' and value > 0;

INST_ID STATISTIC# NAME CLASS VALUE
STAT_ID
------- ---------- ------------------------------------ ----- ----------
----------
1 58 cell writes to flash cache 8 21525
337656778 <-- before the change, only this stat was non-zero, contributed
by LGWR only
1 59 cell overwrites in flash cache 8 3849
2368027758
1 60 cell partial writes in flash cache 8 166
1870362912
1 85 db block gets from cache 8 2848734343
4017839461
...

Oracle Support helped identify the cause of the problem. But we don't know
why the default for us becomes 'none' instead of 'default', even after
dropping and recreating the flashcache as instructed.

--
//www.freelists.org/webpage/oracle-l



Other related posts: