Re: [RFC PATCH 3/5] libsas: dynamic queue depth

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

 



Thanks Mark, I 'll post a patch to raise the default host can queue value,
I'm OK with his change!
--Jack
RE: [RFC PATCH 3/5] libsas: dynamic queue depth
> 
> Good Stuff, 'cept I am worried about the host max queue depth of 128 on
> the pm8001 driver resulting in starvation. I defer to Jack Wang's
> judgement on that point (and will explore separately how we can increase
> the host queue depth reliably on the pm8001).
> 
> Consider this an Ack from me that has an interlock on Jack Wang's Ack
> ...
> 
> Sincerely -- Mark Salyzyn
> 
> -----Original Message-----
> From: Dan Williams [mailto:dan.j.williams@xxxxxxxxx]
> Sent: Tuesday, September 20, 2011 6:11 PM
> To: linux-ide@xxxxxxxxxxxxxxx; linux-scsi@xxxxxxxxxxxxxxx
> Cc: Dave Jiang; Luben Tuikov; jgarzik@xxxxxxxxx;
> JBottomley@xxxxxxxxxxxxx; Jack Wang; Xiangliang Yu; Mark Salyzyn;
> Christoph Hellwig
> Subject: [RFC PATCH 3/5] libsas: dynamic queue depth
> 
> The queue-depth for libsas-attached devices initializes to 32 and can
> only be increased manually via sysfs to a max of 64, while mpt2sas
> attached devices initialize to 254 and dynamically float via the
> midlayer ->change_queue_depth interface.
> 
> No performance regression was observed with this change on the isci
> driver.
> 
> Cc: Christoph Hellwig <hch@xxxxxx>
> Cc: Mark Salyzyn <msalyzyn@xxxxxxxxxxxxxx>
> Cc: Xiangliang Yu <yuxiangl@xxxxxxxxxxx>
> Cc: Jack Wang <jack_wang@xxxxxxxxx>
> Cc: Mark Salyzyn <msalyzyn@xxxxxxxxxxxxxx>
> Cc: Luben Tuikov <ltuikov@xxxxxxxxx>
> Tested-by: Dave Jiang <dave.jiang@xxxxxxxxx>
> Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
> ---
>  drivers/scsi/libsas/sas_scsi_host.c |   39
> ++++++++++++++++-------------------
>  1 files changed, 18 insertions(+), 21 deletions(-)
> 
> diff --git a/drivers/scsi/libsas/sas_scsi_host.c
> b/drivers/scsi/libsas/sas_scsi_host.c
> index 4c6923c..fe08ef0 100644
> --- a/drivers/scsi/libsas/sas_scsi_host.c
> +++ b/drivers/scsi/libsas/sas_scsi_host.c
> @@ -784,8 +784,7 @@ int sas_target_alloc(struct scsi_target *starget)
>  	return 0;
>  }
> 
> -#define SAS_DEF_QD 32
> -#define SAS_MAX_QD 64
> +#define SAS_DEF_QD 256
> 
>  int sas_slave_configure(struct scsi_device *scsi_dev)
>  {
> ______________________________________________________________________
> This email may contain privileged or confidential information, which
should
> only be used for the purpose for which it was sent by Xyratex. No further
rights
> or licenses are granted to use such information. If you are not the
intended
> recipient of this message, please notify the sender by return and delete
it.
> You may not use, copy, disclose or rely on the information contained in
it.
> 
> Internet email is susceptible to data corruption, interception and
> unauthorised amendment for which Xyratex does not accept liability. While
we
> have taken reasonable precautions to ensure that this email is free of
viruses,
> Xyratex does not accept liability for the presence of any computer viruses
in
> this email, nor for any losses caused as a result of viruses.
> 
> Xyratex Technology Limited (03134912), Registered in England & Wales,
> Registered Office, Langstone Road, Havant, Hampshire, PO9 1SA.
> 
> The Xyratex group of companies also includes, Xyratex Ltd, registered in
> Bermuda, Xyratex International Inc, registered in California, Xyratex
> (Malaysia) Sdn Bhd registered in Malaysia, Xyratex Technology (Wuxi) Co
Ltd
> registered in The People's Republic of China and Xyratex Japan Limited
> registered in Japan.
> ______________________________________________________________________
> 

--
To unsubscribe from this list: send the line "unsubscribe linux-ide" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html


[Index of Archives]     [Linux Filesystems]     [Linux SCSI]     [Linux RAID]     [Git]     [Kernel Newbies]     [Linux Newbie]     [Security]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Samba]     [Device Mapper]

  Powered by Linux