Date: Wed, 28 Mar 2007 07:36:09 -0500 From: Eric Anderson <anderson@freebsd.org> To: =?ISO-8859-1?Q?Szab=F3_P=E9ter?= <matyee@mail.alba.hu> Cc: freebsd-geom@freebsd.org Subject: Re: raid3 is slow Message-ID: <460A6139.4040401@freebsd.org> In-Reply-To: <005c01c77134$28e0fce0$6502a8c0@peteruj> References: <003401c7712a$f71ebb60$6502a8c0@peteruj> <eudlg8$pm4$1@sea.gmane.org> <005c01c77134$28e0fce0$6502a8c0@peteruj>
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On 03/28/07 07:25, Szabó Péter wrote: > Yes, consumers are the disks. [..snip..] > #systat -vmstat > > 4 users Load 1.62 1.75 1.82 Mar 28 14:24 > > Mem:KB REAL VIRTUAL VN PAGER SWAP PAGER > Tot Share Tot Share Free in out in out > Act 66488 6968 150740 11396 31172 count > All 1017076 10160975701764 16256 pages > 1 zfod Interrupts > Proc:r p d s w Csw Trp Sys Int Sof Flt cow 4066 total > 1 60 9820 68312106 4237 752 1 195968 wire 1002 0: clk > 79088 act 128 8: rtc > 89.2%Sys 3.0%Intr 3.3%User 0.0%Nice 4.5%Idl 714076 inact 10 10: > fxp > | | | | | | | | | | 29068 cache 1780 11: > ata > =============================================+>> 2104 free 573 14: > ata > 12 daefr 573 15: > ata > Namei Name-cache Dir-cache prcfr > Calls hits % hits % react > 11 10 91 1 pdwake > 4045 pdpgs > Disks ad0 ad1 ad2 ad3 ad6 intrn > KB/t 8.42 8.42 8.42 8.42 5.67 113904 buf > tps 287 287 287 287 1780 133 dirtybuf > MB/s 2.36 2.36 2.36 2.36 9.85 69984 desiredvnodes > % busy 25 26 24 26 99 21586 numvnodes > 17495 freevnodes > > I use mc to copy. > > Matyee Can you send the output of: diskinfo -vt /dev/raid3/nmivol diskinfo -vt /dev/label/nmivol1 Thanks Eric >> Szabó Péter wrote: >> >>> I have a raid3 setup with 5 consumers. it seems everything is all right, >>> but riad is very slow imho, but i don't have any >reference. >> You need to give more accurate information. What are the "consumers" you >> mention? Maybe you mean the disks/components of the RAID? >> >>> Now i copy from raid3 to a single hdd 75GB data. Nothing else run, except >>> ssh, and ftp. Before the copy my load is >0.1, after i star the copy the >>> load is 2.92 or higher, and the machine is very slow. I think this is not >>> normal, or is it? >>> Copy how? By "cp" from shell? >>> My config is: >>> AMD Barton 2500+ with 1GB memory. >>> >>> I stop the copy, load is 0.05, and start again, after a few seconds load >>> is 2.02. > >> Due to the way raid3 works, it's by definition more CPU-intensive than >> most other RAID levels, but it shouldn't be even remotely slow as that. >> Also, since your load is > 2, what are the other CPU intensive tasks? > > _______________________________________________ > freebsd-geom@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-geom > To unsubscribe, send any mail to "freebsd-geom-unsubscribe@freebsd.org"
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