Date: Sat, 07 Feb 2004 21:57:50 -0600 From: Todd Lewis <todd@qdsdirect.com> To: freebsd-performance@freebsd.org Subject: Raid 5 performance Message-ID: <4025B3BE.3020009@qdsdirect.com>
next in thread | raw e-mail | index | archive | help
I am using FreeBSD 4.9, with a 3ware RAID 5
1 gig memory 2.8g p4
Three questions.
1. FreeBSD has a 16k block size. The RAID card is set at 64k
Block size(its sweet spot). My logic tells me that
increasing the block size to 64k would increase disk
read and write access. But, everything I read suggest
going above 64k is dangerous. Are their any recomendations
on performance a stability concerns when increasnig the
block size to 64k when using a RAID controler.
2. The vfs.hirunningspace variable defualts to 1meg. From what I've
read this looks like a buffer. I'm guessing that its set to
1meg becuase most drives have 1~2 megs of memory. So following
that logic and with safety in mind. For drives with 4 megs
cache, I would set vfs.hirunningspace to 2 megs. 8megs of cache
4 megs to vfs.hirunningspace. So, my 64 megs raid control would
have a vfs.hirunningspace 32.
3. Any other stellar performance info would be appriciated.
netstat -m
mbuf usage:
GEN list: 4/480 (in use/in pool)
CPU #0 list: 443/656 (in use/in pool)
Total: 447/1136 (in use/in pool)
Maximum number allowed on each CPU list: 512
Maximum possible: 51200
Allocated mbuf types:
358 mbufs allocated to data
89 mbufs allocated to packet headers
2% of mbuf map consumed
mbuf cluster usage:
GEN list: 12/564 (in use/in pool)
CPU #0 list: 263/304 (in use/in pool)
Total: 275/868 (in use/in pool)
Maximum number allowed on each CPU list: 128
Maximum possible: 25600
3% of cluster map consumed
2020 KBytes of wired memory reserved (32% in use)
0 requests for memory denied
0 requests for memory delayed
0 calls to protocol drain routines
dd if=/dev/da0s1f of=/dev/null bs=1m count=100
code:
100+0 records in
100+0 records out
104857600 bytes transferred in 6.331798 secs (16560478 bytes/sec)
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?4025B3BE.3020009>