Re: experiences beyond 4 GB RAM with 2.4.22

[Andrea Arcangeli <andrea@suse.de>]

On Tue, Sep 09, 2003 at 11:01:12AM +0200, Stephan von Krawczynski wrote:
> Hello,
> 
> lately I upgraded my testbox from 2 to 6 GB ram and found out some oddities I
> would like to hear your opinions.
> The box ran flawlessly and performant with 2 GB - was in fact a real joy.
> After upgrading the ram and recompiling kernel 2.4.22 with support for 64 GB I
> noticed:
> 
> 1) nfs clients see timeouts again, like
> 
> Sep  9 03:37:35 clienta kernel: nfs: server 192.168.1.1 not responding, still
> trying
> Sep  9 03:37:35 clienta kernel: nfs: server 192.168.1.1 OK
> Sep  9 03:37:35 clienta kernel: nfs: server 192.168.1.1 not responding, still
> trying
> Sep  9 03:37:35 clienta kernel: nfs: server 192.168.1.1 OK
> Sep  9 03:41:13 clienta kernel: nfs: server 192.168.1.1 not responding, still
> trying
> Sep  9 03:41:13 clienta kernel: nfs: server 192.168.1.1 OK
> 
> Both are 2.4.22. 192.168.1.1 is the testbox. I saw those with 2GB, but could
> fix it through more nfs-daemons and
> 
>         echo 2097152 >/proc/sys/net/core/rmem_max
>         echo 2097152 >/proc/sys/net/core/wmem_max
> 
> Are these values too small for 6 GB?
> 
> 2) Box is very slow, kswapd looks very active during tar of a local harddisk.
> Interactivity is really bad. Seems vm has a high time looking for free or
> usable pages. Compared to 2 GB the behaviour is unbelievably bad.
> 
> 3) Network performance has a remarkable dropdown during above tar. In fact
> doing simple pings every few minutes shows that quite a lot of them are simply
> dropped, never make it over the ethernet.
> 
> I am really astonished about this. Can some kind soul give me hints or maybe
> patches to try?

for the vm issues my suggestion is to try again with 2.4.22aa1.

Andrea

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