Re: mkfs.xfs error creating large agcount an raid

Marcus Pereira
2011-06-27T04:14:37Z

Em 27-06-2011 00:33, Stan Hoeppner escreveu:
>
> I recommend 3 changes, one of which I previously mentioned:
>
> 1. Use 8 mirror pairs instead of 4
> 2. Don't use striping. Make an mdraid --linear device of the 8 mirrors
> 3. Format with '-d agcount=32' which will give you 4 AGs per spindle
>
> Test this configuration and post your results.

I am thanks for all advices. I will make the tests and post, may take
some time.

About all other messages. My system may not be a Ferrari but its not a
Volks. I certainly do not have that many HDs in fiber channel, but the
sever is a dual core Xeon 6 cores with HT. Linux sees a total of 24
cores, total RAM is 24GB. The HDs are all SAS 15Krpm and the system runs
on SSD. They are dedicated to handle the maildir files and I have
several of those servers running nicely.
But I don’t want to make the thread about my system larger.

Yes, I don’t know much about XFS and Allocation groups, thanks for you
all to help me a bit.

At the end the reason why I opened the thread it the error and the
developers should take some care about that.

Ok, no reason to use that many agcount but giving a "mkfs.xfs: pwrite64
failed: No space left on device" error for me stills seems a bug.
I manage to create a XFS volume with agcount=30000 on a normal device,
no error or warning.
On md or lvm arrays I got that error at some point.

Marcus