test, with striped 4 disk ramdisk, comparing UFS to ZFS

800 MB/s limit test, with striped 4 disk ramdisk, comparing UFS to ZFS

/sbin/mdconfig -d -u md0
/sbin/mdconfig -d -u md1
/sbin/mdconfig -d -u md2
/sbin/mdconfig -d -u md3
/sbin/mdconfig -a -t swap -s 2g -u md0
/sbin/mdconfig -a -t swap -s 2g -u md1
/sbin/mdconfig -a -t swap -s 2g -u md2
/sbin/mdconfig -a -t swap -s 2g -u md3

zpool create zram md0 md1 md2 md3
zfs set atime=off zram

cd /
#run this twice and ignore first result (fills read cache)
gdd if=/tank/bcnasvm1/images/openSUSE-11.4-DVD-x86_64.iso of=zram/testfile bs=1M conv=fdatasync
    4614782976 bytes (4.6 GB) copied, 3.63037 s, 1.3 GB/s

zfs umount zram
zfs mount zram
gdd if=zram/testfile of=/dev/null bs=1M
    4614782976 bytes (4.6 GB) copied, 1.84721 s, 2.5 GB/s

zpool destroy zram

gstripe load
gstripe create -v -s 131072 ufsram md0 md1 md2 md3
newfs /dev/stripe/ufsram
cd /mnt
mkdir test
mount /dev/stripe/ufsram test
gdd if=/tank/bcnasvm1/images/openSUSE-11.4-DVD-x86_64.iso of=test/testfile bs=1M conv=fdatasync
    4614782976 bytes (4.6 GB) copied, 4.25456 s, 1.1 GB/s


umount test
mount /dev/md0 test
ls -l test
find test
gdd if=test/testfile of=/dev/null bs=1M
    (total system hang) ****************

# read cache problem
gdd if=test/testfile of=/dev/null bs=1M
    ?

# read cache clearing hack
cd test
umount /mnt/test
    umount: unmount of /mnt/test failed: Device busy
cd ..
gdd if=test/testfile of=/dev/null bs=1M
    ?