On Thu, Oct 30, 2008 at 8:15 PM, Sumit Gupta <[EMAIL PROTECTED]> wrote:
>
> On Oct 30, 2008, at 9:25 AM, Cyril Plisko wrote:
>>
>> Sumit,
>>
>> thanks for explanation. As for the duration of the sleep - I was
>> wondering about calling kmem_alloc() with KM_SLEEP vs KM_NOSLEEP
>> inside LU entry point. I have no idea how long this will sleep.
>
>        It is ok to use KM_SLEEP inside LU entry points as in most cases you
> will have memory and the call wont sleep. If you are running out of
> memory then your system performance is not going to be good anyway.
> Which is what will happen if the worker sleeps for a long time.

An alternative is to stick to KM_NOSLEEP and use deferred execution
via stmf_task_poll_lu() call on failure.

Regards,
Andrey

>
>
>> I also didn't quite grok your note on using lu_poll. Can you please
>> give some example ?
>
>        The framework provides a mechanism for the LU to say "I cannot
> handle this task right now, call me back later". The LU does so by
> calling stmf_task_poll_lu() and the framework later on calls the
> lu_poll entry point. This is useful for very slow tasks like
> rewinding a tape or ejecting media etc. This is also documented in
> detail in the stmf spec.
>
> Sumit
>
>>
>>>
>>> Sumit
>>>
>>> On Oct 29, 2008, at 3:21 PM, Cyril Plisko wrote:
>>>
>>>> Hello,
>>>>
>>>> I have another question on COMSTAR:
>>>>
>>>> where can I find the information about the context of the LU entry
>>>> points ? I am trying to figure out when am I allowed to sleep...
>>>>
>>>> --
>>>> Regards,
>>>>        Cyril
>>>> _______________________________________________
>>>> storage-discuss mailing list
>>>> [email protected]
>>>> http://mail.opensolaris.org/mailman/listinfo/storage-discuss
>>>
>>>
>>
>>
>>
>> --
>> Regards,
>>         Cyril
>
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