On Fri, 25 Jan 2008 02:50:16 +1100, Rene Salmon <salmr0@xxxxxx> wrote:
>> >
>> > General rule of thumb at the moment is 128MB of RAM/TB of
filesystem
>> > plus 4MB/million inodes on that filesystem.
>>
>> Did this change lately? I found the rule of thumb: 2 GB RAM for 1
TB
>> of disk storage + some RAM per x inodes.
>
> The above is based on actual theoretical usage, the below:
>
>> http://oss.sgi.com/archives/xfs/2005-08/msg00045.html
>
> was based on reported usage on during live repair runs.
>
> I think Barry discovered the difference to be things external
> to repair such as heap fragmentation and has since corrected
> the worst of the issues so requirements are, in general,
> much closer to the theoretical numbers now.
Yes, quite a few memory improvements have been made.
Right now, I can repair a 9TB filesystem with ~150 million inodes
in 2GB of RAM without going to swap using xfs_repair 2.9.4 and
with no custom/tuning/config options.
Thanks. That is great news about the memory improvements. We currently
run SLES 10 SP1 which comes with:
hpcxe005:# xfs_repair -V
xfs_repair version 2.8.16
others come with:
hpcxe001:~ # xfs_repair -V
xfs_repair version 2.9.2
Did the memory improvements make it into 2.8.16? How about 2.9.2? If not
i take it we can download the latest source and just have the 2.9.4
xfs_repair binary laying around in case we ever need to use it. Would
using a 2.9.4 xfs_repair binary on a 2.8.16 created xfs file system
cause any problems?
The memory improvements showed up in 2.9.2.
As Ralf said, xfs_repair can always fix older mkfs'ed filesystems.
Regards,
Barry.
|