inside storage. part1. md raid
запомним:
mdadm --create /dev/md6 --level=6 -n4 --chunk=512 /dev/sd{a,b,c,d}1
mkfs.ext3 -L STORAGE -b 4096 -E stride=128 /dev/md6
usefull perfomance script
#!/bin/bash for cache_size in 256 512 768 1024 2048 4096 8192 16834 32768; do for i in {1..3}; do echo ${cache_size} > /sys/block/md0/md/stripe_cache_size sync echo 3 > /proc/sys/vm/drop_caches echo "stripe_cache_size: ${cache_size} (${i}/3)" # for write dd if=/dev/zero of=/dev/md0 bs=3145728 count=5460 # for read dd if=/dev/md0 of=/dev/null bs=3145728 count=5460 done done http://romanrm.ru/mdadm-raid http://peterkieser.com/2009/11/29/raid-mdraid-stripe_cache_size-vs-write-transfer/
mdadm --create /dev/md6 --level=6 -n4 --chunk=512 /dev/sd{a,b,c,d}1
mkfs.ext3 -L STORAGE -b 4096 -E stride=128 /dev/md6
usefull perfomance script
#!/bin/bash for cache_size in 256 512 768 1024 2048 4096 8192 16834 32768; do for i in {1..3}; do echo ${cache_size} > /sys/block/md0/md/stripe_cache_size sync echo 3 > /proc/sys/vm/drop_caches echo "stripe_cache_size: ${cache_size} (${i}/3)" # for write dd if=/dev/zero of=/dev/md0 bs=3145728 count=5460 # for read dd if=/dev/md0 of=/dev/null bs=3145728 count=5460 done done http://romanrm.ru/mdadm-raid http://peterkieser.com/2009/11/29/raid-mdraid-stripe_cache_size-vs-write-transfer/