[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Re: Temporary 'lock-up' under heavy write, MegaRAID RAID-5

On Wednesday, 09.11.2005 at 10:46 +0000, Dave Ewart wrote:

> System:          4-way Opteron, generic Debian Sarge AMD64
> RAID controller: LSI Logic MegaRAID 320-1, 64MB cache
> RAID config:     Three 146GB 15K SCSI/320 disks, RAID-5
> Kernel:          2.6.14 SMP, includes megaraid driver
> The above system is incredibly fast under almost all conditions, except
> when writing very large files (say, 100s of MB, or even GB).  When
> writing such files, the system effectively locks-up for many seconds -
> typically, for as long as it takes to finish writing/flushing the file
> to disk.  This lock-up affects all other processes: local text editor
> sessions, workstations with /home NFS-mounted, [...]

A partial solution to the lock-up for NFS-mounted /home workstations:
set the NFS mount option 'async', rather than let it assume the default
of 'sync' ... oops.

Dave Ewart
Computing Manager, Cancer Epidemiology Unit
Cancer Research UK / Oxford University
PGP: CC70 1883 BD92 E665 B840 118B 6E94 2CFD 694D E370
Get key from http://www.ceu.ox.ac.uk/~davee/davee-ceu-ox-ac-uk.asc
N 51.7518, W 1.2016

Attachment: signature.asc
Description: Digital signature

Reply to: