[gpfsug-discuss] Quotas, replication and hsm

Bryan Banister bbanister at jumptrading.com
Wed Oct 28 13:25:27 GMT 2015

I'm not sure what kind of report you're looking for, but the `du` command has a "--apparent-size" option that has this description:
              print apparent sizes, rather than disk usage; although the apparent size is usually smaller, it may be larger due to holes in (âsparseâ) files, internal fragmentation, indirect blocks, and the like

This can be used to get the actual amount of space that files are using.

I think that mmrepquota and mmlsquota show twice the amount of space of the actual file due to the replication, but somebody correct me if I'm mistaken.

I also would like to know what the output of the ILM "LIST" policy reports for KB_ALLOCATED for replicated files.  Is it the replicated amount of data?


-----Original Message-----
From: gpfsug-discuss-bounces at spectrumscale.org [mailto:gpfsug-discuss-bounces at spectrumscale.org] On Behalf Of Dan Foster
Sent: Wednesday, October 28, 2015 5:06 AM
To: gpfsug main discussion list
Subject: Re: [gpfsug-discuss] Quotas, replication and hsm

On 27 October 2015 at 17:28, Simon Thompson (Research Computing - IT
Services) <S.J.Thompson at bham.ac.uk> wrote:
> Hi,
> If we have replication enabled on a file, does the size from ls -l or du return the actual file size, or the replicated file size (I.e. Twice the actual size)?.
> From experimentation, it appears to be double the actual size, I.e. Taking into account replication of 2.
> This appears to mean that quotas have to be double what we actually want to take account of the replication factor.
> Is this correct?

This is what we obverse here by default and currently have to double our fileset quotas to take this is to account on replicated filesystems.

You've reminded me that I was going to ask this list if it's possible to report the un-replicated sizes? While the quota management is only a slight pain, what's reported to the user is more of a problem for us(e.g. via SMB share / df ). We're considering replicating a lot more of our filesystems and it would be useful if it didn't appear that everyones quotas had just doubled overnight.

Dan Foster | Senior Storage Systems Administrator | IT Services _______________________________________________
gpfsug-discuss mailing list
gpfsug-discuss at spectrumscale.org


Note: This email is for the confidential use of the named addressee(s) only and may contain proprietary, confidential or privileged information. If you are not the intended recipient, you are hereby notified that any review, dissemination or copying of this email is strictly prohibited, and to please notify the sender immediately and destroy this email and any attachments. Email transmission cannot be guaranteed to be secure or error-free. The Company, therefore, does not make any guarantees as to the completeness or accuracy of this email or any attachments. This email is for informational purposes only and does not constitute a recommendation, offer, request or solicitation of any kind to buy, sell, subscribe, redeem or perform any type of transaction of a financial product.

More information about the gpfsug-discuss mailing list