On 22 January 2013 17:28, Bill Davidsen <davidsen(a)tmr.com> wrote:
Ian Malone wrote:
>
> Hi,
>
> Is anyone else seeing problems with F16 ext4? I recently moved my
> install onto a new harddisc (which is reporting SMART is fine after
> running a full test) and did that by making a new ext4 fs (previously
> ext3) then rsyncing across. I'm now seeing occasional system 'freezes'
> (not hard freezes, but programs can fail to start or freeze. Yesterday
I have multiple TB running on fc16+ext4, and have not seen any
problems of
any kind with the filesystem. I do occasionally see a hang, this happens
with rsync if you copy something large to a machine with significant memory,
at the end rsync does a sync() I believe (if it was doing fsync() I think
the pain would be spread) and the system is emptying the i/o buffers to
disk. A typical single disk will write at 50-100MB/s and if you have 4GB or
more of backed up data, it will get slow. There are disk tuning tips you can
use to spread the pain, but it makes the copy of small files run slower in
many cases.
If you have a lot of small files, your journal may be full of incomplete
transactions. The solution is to make the journal larger, I don't know if
modifying the journal after the fact will change that, or even if it's the
problem. I have played with putting journal on a faster device, 10k rpm
drive, SSD, or memory (yes, just for testing, I know it's unsafe). Faster
journal makes things faster with many small files.
Lots of thoughts for you to check against your particular problems.
Any way to check the journal for incomplete transactions? Except for
immediately after a crash the parition comes up clean in an e2fsck
from a livecd. It made three clean passes through memtest, so I don't
think that's the issue.
--
imalone
http://ibmalone.blogspot.co.uk