Re: Socket Direct Protocol: help (2)

Amir Vadai
2010-04-14T15:16:13Z

ok - actually I used it in an early version of SDP before changing to FMR...

- Amir

On 04/14/2010 06:08 PM, Steve Wise wrote:
> Amir Vadai wrote:
>
>> 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?
>>
>>
>>
> ib_alloc_fast_reg_mr(), ib_alloc_fast_reg_page_list() and friends, plus
> the IB_WR_FAST_REG_MR work request.
>
>
>
>> 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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>>>>>
>>>>>
>>>>>
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>>>
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