[lustre-discuss] OST create_count

[Emyr James]

Hi,

We have lustre 2.5. We had some unbalanced OSTs so we closed them to new files by setting max_create_count to 0. After rebalancing we now want to re-open these OSTs. Setting max_create_count back to 20,000 caused things to hang. I believe this is because we didn't also set create_count to a non-zero value.

https://jira.whamcloud.com/browse/LU-11605

Closing the OSTs brought everything back to 'normal' again.

I had a look but couldn't find what the difference between max_create_count and create_count is, nor hints on setting these values.

max_create_count always seems to be set to 20,000. Why is this a good value? What are good values for create_count ?

Many thanks,

Emyr James
Head of Scientific IT
CRG -Centre for Genomic Regulation
C/ Dr. Aiguader, 88
Edif. PRBB
08003 Barcelona, Spain
Phone Ext: #1098