So Bob,
Yes, we too have observed an uncharacteristic lag on the correction of the
internal quota accounting on GPFS since we updated from version 3.3 to version
4.x some 7-8 years ago. That lag remains through version 5.0.x as well. And it
persisted through several appliances (DDN, G200, GSS, ESS and now DSS-G). In
our university environment there is also a lot of data churning, in particular
small files.
The workaround has always been to periodically run mmcheckquota on the top
independent fileset to expedite that correction (I have a crontab script that
measures the relative size of the in-dought columns on the mmrepquota report,
size and inodes, and if either exceeds 2% for any USR/GRP/FILESET I run
mmrepquota)
We have opened supports calls with IBM about this issue in the past, and we
never got a solution, to possibly adjust some GPFS configuration parameter, and
have this correction done automatically. We gave up.
And that begs the question: what do you mean by "... 5.0.4-4 ... that has a fix for
mmcheckquota"? Isn't mmcheckquota zeroing the in-doubt columns when you run it?
The fix should be for gpfs (something buried in the code over many versions).
As far as I can tell there has never been anything wrong with mmcheckquota.
Thanks
Jaime
On 5/18/2020 08:59:09, Cregan, Bob wrote:
Hi,
At Imperial we have been experiencing an issue with SS 5.0.x and quotas. The main
symptom is a slow decay in the accuracy of reported quota usage when compared to the
actual usage as reported by "du". This discrepancy can be as little as a few
percent and as much as many X100% . We also sometimes see bizarre effects such negative
file number counts being reported.
We have been working with IBM and have put in the latest 5.0.4-4 (that has a
fix for mmcheckquota) that we have been pinning our hopes on, but this has not
worked.
Is anyone else experiencing similar issues? We need to try and get an idea if
this is an issue peculiar to our set up or a more general SS problem.
We are using user and group quotas in a fileset context.
Thanks
*Bob Cregan*
HPC Systems Analyst
Information & Communication Technologies
Imperial College London,
South Kensington Campus London, SW7 2AZ
T: 07712388129
E: b.cre...@imperial.ac.uk
W: www.imperial.ac.uk/ict/rcs <http://www.imperial.ac.uk/ict/rcs>
_1505984389175_twitter.png @imperialRCS @imperialRSE
1505983882959_Imperial-RCS.png
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