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Re: high load, no bottleneck



> I re-enabled -o log and did the dd test again on NetBSD 6.0 with the
> patch you posted and vfs.wapbl.verbose_commit=2
I wouldn't expect anything interesting from this, but maybe hannken@ does.

> Running my stress test, which drives load to insane values:
How often do these log flushes occur?

During the stess phase, what does
        iostat -D -x -w 1
show for the raid and for the components, especially in the time column?

During the stress, do you see small synchronous writes in NFS traffic?

I attach two small shell scripts I wrote to extract statistics from tcpdump 
output. Both operate either on a pcap file, e.g. the output of
        tcpdump ... -s slen -w file port nfs
(where I don't remember what the minimum slen is to capture all relevant info)
or a textual tcpdump -vvv output (which is usually smaller), e.g.
        tcpdump ... -s 0 -vvv port nfs >file

As output, you get a list of NFS calls and a count (nfsstat) or a list of write 
calls ordered by size/sync and their counts.

Attachment: nfsstat.sh
Description: Bourne shell script

Attachment: nfswritestat.sh
Description: Bourne shell script



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