diff options
| author | Mark Haverkamp <markh@osdl.org> | 2006-01-11 09:28:29 -0800 |
|---|---|---|
| committer | James Bottomley <jejb@mulgrave.(none)> | 2006-01-12 11:55:01 -0600 |
| commit | db39363c029cd9e74661ef059a17785d1c62a851 (patch) | |
| tree | 68fa6ae11b646103cc5a115400dc753a04ef2c43 /drivers/scsi/aacraid/aacraid.h | |
| parent | 7686f132653fa3d52d45c3f021215f714094f1ca (diff) | |
[SCSI] aacraid: 17 element sg performance update
Received From Mark Salyzyn.
The Jaguar and Corsair class of adapters (2410, 2810, 2610, 21610, CERC)
perform better (about 10% better read performance, write performance
neutral) with current Firmware if the OS limits the number of scatter
gather elements to 17 per request.
Signed-off-by: Mark Haverkamp <markh@osdl.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Diffstat (limited to 'drivers/scsi/aacraid/aacraid.h')
| -rw-r--r-- | drivers/scsi/aacraid/aacraid.h | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/scsi/aacraid/aacraid.h b/drivers/scsi/aacraid/aacraid.h index 30fd8d6e3f31..66dbb6d2c506 100644 --- a/drivers/scsi/aacraid/aacraid.h +++ b/drivers/scsi/aacraid/aacraid.h @@ -532,6 +532,13 @@ struct aac_driver_ident #define AAC_QUIRK_MASTER 0x0008 /* + * Some adapter firmware perform poorly when it must split up scatter gathers + * in order to deal with the limits of the underlying CHIM. This limit in this + * class of adapters is 17 scatter gather elements. + */ +#define AAC_QUIRK_17SG 0x0010 + +/* * The adapter interface specs all queues to be located in the same * physically contigous block. The host structure that defines the * commuication queues will assume they are each a separate physically |