question concerning proper usage of kernel
variables net.bpf.bufsize and vm_kmem_size_max
Jin Guojun [VFFS]
jin at george.lbl.gov
Wed Jul 26 23:20:57 UTC 2006
R. B. Riddick wrote:
>--- Raymond Owens <owensr at comcast.net> wrote:
>>Can VM_KMEM_SIZE_MAX be set manually with sysctl?
>No, but you could set it with this procedure:
>1. Insert the lines
>That should change those values...
>I wonder, why your box needs such a big buffer? Do u have network traffic
>bursts or so?
Regardless what purpose is for, the net.bpf.bufsize should never
set above hardware cache size. The best (optimal size) is 50% - 80%
of the hardware cache size, unless original BPF is modified in some
way I do not know.
Such high bufsize will degrade performance.
------------ Jin Guojun ----------- v --- jin at george.lbl.gov ---
Distributed Systems Department http://www.dsd.lbl.gov/~jin
Lawrence Berkeley National Laboratory, Berkeley, CA 94720
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