[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]

Re: Write to ext3 fs -> kjournald goes bananas



Peter Schuller <peter schuller infidyne com> wrote:
>
> Hello,
> 
> we have just observed a rather annoying behavior one of our servers.
> Specifically, when writing data to a file on an ext3fs filesystem at
> around 1.5 MB/sec, network connectivity suddently started to show
> signs of lag.
> 
> The ping would spike up to ~1 second every 5 seconds or so. This affects
> the server in question and all hosts routing traffic through it (i.e.,
> it's not a userland-only problem).
> 
> When this happens, the load skyrockets (> 10 on an otherwise mostly idle
> server) and kjournald can be seen consuming CPU cycles like mad.
> 

Usually, this sort of thing is caused by an IDE subsystem which is not
running in DMA mode.

You can use `hdparm /dev/hda' to display the current DMA setting.





[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]