From mboxrd@z Thu Jan 1 00:00:00 1970 From: Zoltan Szecsei Subject: Array read 3 time slower to read after data fully loaded Date: Thu, 18 Nov 2010 07:30:14 +0200 Message-ID: <4CE4B9E6.1040802@geograph.co.za> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Sender: linux-raid-owner@vger.kernel.org To: linux-raid@vger.kernel.org List-Id: linux-raid.ids Hi, Can anyone please explain this to me? =46or the last >30 hours I have been loading some 2.5TB of 200-400MB ti= ff=20 images, from another PC on our internal network, onto this new array. Yesterday, during this load process, I copied 10 of these files (about=20 2.5GB) from the array onto the /home directory of the same system. It took 33 seconds, equating to some 75MB/s. This morning I came in to find that the load process had finished, so I= =20 deleted the 10 test files from /home, and redid the identical copy test= =20 (using bash-history, so: identical). It took 123 seconds, equating to some 20MB/s. Que? (as in Manuel from Faulty Towers :-) ) Thanks & regards, Zoltan root@gs0:/home/geograph# uname -a Linux gs0 2.6.32-25-generic #45-Ubuntu SMP Sat Oct 16 19:52:42 UTC 2010= =20 x86_64 GNU/Linux root@gs0:/home/geograph# mdadm -V mdadm - v3.1.4 - 31st August 2010 root@gs0:/home/geograph# lvm version LVM version: 2.02.54(1) (2009-10-26) Library version: 1.02.39 (2009-10-26) Driver version: 4.15.0 root@gs0:/home/geograph# df #ext4 =46ilesystem 1K-blocks Used Available Use% Mounted on /dev/sdi7 426559760 9494844 395396872 3% /home /dev/mapper/geo_vg0-geo_lvm0 11536635672 2530042680 8889387468 23% /mnt/geo_l= vm0 root@gs0:/home/geograph# --=20 =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D Zoltan Szecsei PrGISc [PGP0031] Geograph (Pty) Ltd. P.O. Box 7, Muizenberg 7950, South Africa. 65 Main Road, Muizenberg 7945 Western Cape, South Africa. 34=B0 6'16.35"S 18=B028'5.62"E Tel: +27-21-7884897 Mobile: +27-83-6004028 =46ax: +27-86-6115323 www.geograph.co.za =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D ----- No virus found in this message. Checked by AVG - www.avg.com Version: 10.0.1153 / Virus Database: 424/3262 - Release Date: 11/17/10 -- To unsubscribe from this list: send the line "unsubscribe linux-raid" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html