Re: Socket Direct Protocol: help (2)

Amir Vadai
2010-04-14T15:03:57Z

You are right - I missed it.

Andrea, Please open a bug at bugzilla (https://bugs.openfabrics.org) -
so that you will be notified as soon as I will fix SDP not use FMR if
not supported.

As to fastreg_mrs support - I don't know this mechanism. Do you mean FRWR?

Thanks,
Amir

On 04/14/2010 05:54 PM, Steve Wise wrote:
> Hey Amir,
>
> I don't think this helps because sdp_add_device() will not add rdma
> devices that fail to create fmr pools.
>
> So I guess you could key off of fmr pool failures and set
> sdp_zcopy_thresh to 0 and allow the device to be used?
>
> But what we really need is sdp support for fastreg_mrs as an
> alternative to fmrs.
>
>
> Steve.
>
>
> Amir Vadai wrote:
>
>> Hi,
>>
>> FMR are being used only in a special mode called ZCopy.
>>
>> You could disable this mode by setting the module paramter
>> sdp_zcopy_thresh to 0, or by issuing:
>> # echo 0 > /sys/module/ib_sdp/parameters/sdp_zcopy_thresh
>>
>> This means that you won't get the benefits of Zero-copy.
>>
>> - Amir
>>
>> On 04/14/2010 11:51 AM, Andrea Gozzelino wrote:
>>
>>
>>> On Apr 13, 2010 10:22 PM, "Tung, Chien Tin" <chien.tin.tung-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
>>> wrote:
>>>
>>>
>>>
>>>
>>>>>>> Chien, does the NE020 support FMRs? I looked at the nes ofed-1.5
>>>>>>> code
>>>>>>> and it appears to do nothing in the map_phys_fmr functions.
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>> We never implemented map_phys_fmr. Is it relevant to the # of SGEs?
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>> No, but SDP uses FMRs. I don't think it will run without FMR support.
>>>>>
>>>>>
>>>>>
>>>>>
>>>> Good to know. Thanks.
>>>>
>>>> Chien
>>>>
>>>>
>>>>
>>>>
>>>>
>>> Hi Steve and Chien,
>>>
>>> I understand that NE020 cards have problem with SDP connected with
>>> map_phy_fmr (FMR stands for Fast Memory Region).
>>> Is it possible to solve/fix this point?
>>> If yes, have you an idea about the time that is necessary to code
>>> development/build?
>>> If no, can you suggest me a card that supports SDP protocol?
>>>
>>> I work on NE020 cards from February 2010 for an INFN experimental
>>> proposal, called REDIGO (Read out at 10 Gbits/s), about the data
>>> acquisition and movement systems. The covergence of storage protocols
>>> around 10 Gigabits/s Ethernet protocols shows that one way could be the
>>> Remote Direct Memory Access (RDMA). The goals are the investigations of
>>> latency time, the throughput, the buffer size schemes and finally the
>>> global event building bandwidth.
>>>
>>> Do you know if NE020 cards have problems with librdma (RDMA procedures,
>>> in general) and / or with MPI versions?
>>>
>>> Thank you very much,
>>> Andrea
>>>
>>> Andrea Gozzelino
>>>
>>> INFN - Laboratori Nazionali di Legnaro (LNL)
>>> Viale dell'Universita' 2
>>> I-35020 - Legnaro (PD)- ITALIA
>>> Tel: +39 049 8068346
>>> Fax: +39 049 641925
>>> Mail: andrea.gozzelino-PK20h7lG/Rc1GQ1Ptb7lUw@public.gmane.org
>>>
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