Re: SQ overflow seen running isert traffic with high block sizes

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

 



Hey Ram, CC'ing target-devel for iser-target related posts.

We are hitting SQ overflow on iSER target side with high block sizes over RoCE
(see dmesg output below).

We are using Q-Logic/Cavium NIC with a capability of 4 sges.

That's somewhat expected if the device has low max_sge. It was decided
that queue_full mechanism is not something that iser-target should
handle but rather the iscsi-target core on top.

You probably should not get into aborts though... Does the I/O complete?
or does it fail?

Is this upstream? is [1] applied?

I could come up with some queue-full handling in isert that will be more
lightweight, but I'd let Nic make a judgment call before I do anything.

[1]:
commit a4467018c2a7228f4ef58051f0511bd037bff264
Author: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx>
Date:   Sun Oct 30 17:30:08 2016 -0700

    iscsi-target: Propigate queue_data_in + queue_status errors

    This patch changes iscsi-target to propagate iscsit_transport
    ->iscsit_queue_data_in() and ->iscsit_queue_status() callback
    errors, back up into target-core.

    This allows target-core to retry failed iscsit_transport
    callbacks using internal queue-full logic.

    Reported-by: Potnuri Bharat Teja <bharat@xxxxxxxxxxx>
    Reviewed-by: Potnuri Bharat Teja <bharat@xxxxxxxxxxx>
    Tested-by: Potnuri Bharat Teja <bharat@xxxxxxxxxxx>
    Cc: Potnuri Bharat Teja <bharat@xxxxxxxxxxx>
    Reported-by: Steve Wise <swise@xxxxxxxxxxxxxxxxxxxxx>
    Cc: Steve Wise <swise@xxxxxxxxxxxxxxxxxxxxx>
    Cc: Sagi Grimberg <sagi@xxxxxxxxxxx>
    Signed-off-by: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx>
--
To unsubscribe from this list: send the line "unsubscribe linux-rdma" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Photo]     [Yosemite News]     [Yosemite Photos]     [Linux Kernel]     [Linux SCSI]     [XFree86]
  Powered by Linux