[gpfsug-discuss] Inode scan optimization
Tomasz.Wolski at ts.fujitsu.com
Tomasz.Wolski at ts.fujitsu.com
Thu Feb 8 10:35:54 GMT 2018
Hello All,
A full backup of an 2 billion inodes spectrum scale file system on V4.1.1.16 takes 60 days.
We try to optimize and using inode scans seems to improve, even when we are using a directory scan and the inode scan just for having a better performance concerning stat (using gpfs_stat_inode_with_xattrs64). With 20 processes in parallel doing dir scans (+ inode scans for stat info) we have decreased the time to 40 days.
All NSDs are dataAndMetadata type.
I have the following questions:
· Is there a way to increase the inode scan cache (we may use 32 GByte)?
o Can we us the "hidden" config parameters
§ iscanPrefetchAggressiveness 2
§ iscanPrefetchDepth 0
§ iscanPrefetchThreadsPerNode 0
· Is there a documentation concerning cache behavior?
o if no, is the inode scan cache process or node specific?
o Is there a suggestion to optimize the termIno parameter in the gpfs_stat_inode_with_xattrs64() in such a use case?
Thanks!
Best regards,
Tomasz Wolski
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://gpfsug.org/pipermail/gpfsug-discuss_gpfsug.org/attachments/20180208/cacc9a69/attachment-0001.htm>
More information about the gpfsug-discuss
mailing list