> Did you try 'disklabel -w da0 auto'?
Yup - it also complained.
> No, it would cause a higher I/O load. Vinum doesn't transfer entire
> stripes, it transfers what you ask for. With a large stripe size, the
> chances are higher that you can perform the transfer with only a
> single I/O.
Even if I'm using really large reads?
> > I'm seeing 4.4MB/s if I read from an individual disk, but only about
> > 5.6MB/s when reading from the striped volume.
> How many concurrent processes? Remember that striping doesn't buy you
> anything with a single process. You might like to try rawio
> (ftp://ftp.lemis.com/pub/rawio.tar.gz) and see what that tells you.
OK, I was just using good ol' dd, with dd if=/cfs/foo of=/dev/null bs=2m
> > Looking at the systat display, the 8k fs blocks do seem to be
> > clustered into larger requests, so I'm not too worried about the FS
> > block size. What have people observed with trying larger FS block
> > sizes?
> I don't know if anybody has tried larger FS blocks than 8 kB. I once
> created a file system with 256 kB blocks (just to see if it could be
> done). I also tried 512 kB blocks, but newfs died of an overflow.
> I'd expect that you would see a marked drop in performance, assuming
> that it would work at all.
OK. The minimum data size read from these files tends to be about 10k. I'll have to try this all with a real app.
The views expressed above are not those of PGS Tensor.
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