sysbench / fileio - Linux vs. FreeBSD

[Matthew Dillon]

:>     It would be interesting to see a blogbench comparison between UFS
:>     and ZFS on the same hw/disk.
:
:
:I'll do it, just tell me how do you want to run the tests.
:
:The system params are:
:
:8GB Memory
:2x72GB SCSI HDD
:2x3.4Ghz Xeon
:Overall: Dell Poweredge 1850. With no raid installed.
:
:I'm waiting the benchmark options to run.
:
:- -- 
:Adam PAPAI

    With 8G of ram blogbench should blow out the system caches at around
    blog 1000-1600, though it also depends on the maximum number of
    vnodes supported by the system.  One of the two (VM pages or vnode
    limit) will be hit.

    All you need to do is run blogbench with enough iterations to ensure
    that the run eventually blows out the system caches.  200 or 300 should
    do the job.  It's easy to tell when the system cache gets blown out from
    looking at the output.

    Run something like the following script for a few hours.  You want to
    get at least four full runs under your belt for each filesystem to
    factor out edge cases.

    For the filesystem setup it would be cool to test both the single-drive
    case and a simple non-redundant interleaved or mirrored setup (double
    the read bandwidth).  With UFS use default parameters with softupdates
    turned on (I'd say also without SUJ).  With ZFS I don't know how best
    to tune it, try to find a ZFS setup that performs decently. 

    However, be sure to turn off compression and dedup (if those fs options
    are available), because blogbench basically just writes all-zeros which
    is highly compressable/collapsable and would skew the results badly.

					-Matt

#!/bin/csh
#
# /build is the filesystem under test.

set i = 0
while(1)
    set name = `printf "bench%05d" $i`
    echo $name
    if ( ! -d /build/blogs/$name ) then
        mkdir -p /build/blogs/$name
        blogbench --iterations=200 -d /build/blogs/$name
	sleep 120
    endif
    @ i = $i + 1
end