[LU-4665] utils: lfs setstripe to specify OSTs

• Type: New Feature
• Resolution: Fixed
• Priority: Critical
• Fix Version/s: Lustre 2.7.0
• Labels: llnl
• Severity: 3
• Assignee: Emoly Liu
• Reporter: Jinshan Xiong (Inactive)

Description

#5: Sparse OST indicies
#6: Setstripe for specified OSTs.

Issue Links

• is related to: LU-5170 lfs usability
• is related to: LU-5878 lfs migrate sends file to stdout
• is related to: LU-9392 lfs migrate -o and lfs setstripe -o should pick OST from ost_list
• is related to: LU-8417 setstripe -o does not work on directories
• is related to: LU-3840 llapi_layout API design discussion
• is related to: LU-6135 improved support for selecting specific OSTs for files

Comments

[Oleg Drokin]

Ah, I also noticed that the current patch returns error if ldo_def_stripe_offset is not in the list of OSTs, but failed to consider that -1 should mean "use something that makes sense". This too needs to be addressed. Esp. in light of the previous comment

[Oleg Drokin]

This feature totally needs a way to specify ost_count in addition to OST list that way we do not force user to do their own load balancing.
Say I have a set of 100 OSTs that are local enough for my set of nodes, but I only need a striping of 4...
We seriously should consider adding this as a follow on patch.

[Peter Jones]

Emoly

Could you please assist with reviewing these patches?

Thanks

Peter

[James A Simmons]

Not with the patch directly. I did see failures due to the new layout api using fsetxattr instead of the ioctl for setting stripes. There was code in ll_setxattr that if sent in stripe_offset was set to zero it was set to -1 which meant a random OST was picked instead of OST 0. The base LU-2182 patch which this work depends on should now behave properly. We will see once Maloo is done.

[Jinshan Xiong (Inactive)]

Is there any problems with the patch?

[James A Simmons]

Yes. In fact I'm debugging it right now.

[Jinshan Xiong (Inactive)]

Hi James,

Are you still working on this? We're going to land this patch in 2.7.

[James A Simmons]

Started integrating this work with LU-2182.

[Shuichi Ihara (Inactive)]

Is this still for regular file only? What's other porject or dependency to support specific OST selection for directory?

[Jinshan Xiong (Inactive)]

Hi James,

Please feel free to pick it up and move it forward. Thanks

Jinshan

[James A Simmons]

If you don't have the time Jinshan I will gladly do the work.