I am actually also away. It looks like something in XrdPosix is forcing
new connections. I will have a closer look once I am back on Wednesday.
Lukasz
On 8/26/13 11:46 PM, Lukasz Janyst wrote:
> I call it a trick because the only context I have seen it used in is
> forcing new physical connections instead of reusing existing ones.
>
> Lukasz
>
> On 8/26/13 11:45 PM, Lukasz Janyst wrote:
>> Hi Matevz,
>>
>> Andy's on vacation until 2nd Sep.
>>
>> Lukasz
>>
>> On 8/26/13 11:28 PM, Matevz Tadel wrote:
>>> Hi Lukasz, Everybody,
>>>
>>> On 8/24/13 5:55 AM, Lukasz Janyst wrote:
>>>> Yes, in fact the username "trick" to trigger the new connections
>>>> would still
>>>> work with the new client and that's likely what is happening here.
>>>
>>> Hmmh ... why do you call it a trick? And where are the usernames
>>> coming from? This is all running within a single xrootd-proxy
>>> process ... so it is always the same user, I don't see how this
>>> could change in any way. (On server side and in monitoring, this is
>>> obviously a different user, as port number is also combined into it.)
>>>
>>> Anyway ... this seems a really bad idea for the proxy :)
>>>
>>> Here is a dump of server/monitoring-side usernames for a bunch of
>>> consecutive file-close events. You can see some of them get reused
>>> ... but 105 of such connections stayed for 3 days+ (after reading
>>> ~300 files with 300 XrdCls in a single process).
>>>
>>> * 413974 * alja.2636:[log in to unmask] *
>>> * 415017 * alja.2636:[log in to unmask] *
>>> * 416011 * alja.2636:[log in to unmask] *
>>> * 416476 * alja.2636:[log in to unmask] *
>>> * 417680 * alja.2636:[log in to unmask] *
>>> * 419305 * alja.2636:[log in to unmask] *
>>> * 419376 * alja.2636:[log in to unmask] *
>>> * 419520 * alja.2636:[log in to unmask] *
>>> * 419599 * alja.2636:[log in to unmask] *
>>> * 419942 * alja.2636:[log in to unmask] *
>>> * 420628 * alja.2636:[log in to unmask] *
>>> * 421065 * alja.2636:[log in to unmask] *
>>> * 422202 * alja.2636:[log in to unmask] *
>>> * 422688 * alja.2636:[log in to unmask] *
>>> * 423059 * alja.2636:[log in to unmask] *
>>> * 423080 * alja.2636:[log in to unmask] *
>>> * 424121 * alja.2636:[log in to unmask] *
>>> * 424264 * alja.2636:[log in to unmask] *
>>> * 431576 * alja.2636:[log in to unmask] *
>>> * 488603 * alja.2636:[log in to unmask] *
>>> * 489027 * alja.2636:[log in to unmask] *
>>> * 489340 * alja.2636:[log in to unmask] *
>>> * 494316 * alja.2636:[log in to unmask] *
>>> * 494699 * alja.2636:[log in to unmask] *
>>> * 496100 * alja.2636:[log in to unmask] *
>>>
>>>> In fact you can see what is exactly happening if you set the
>>>> XRD_LOGLEVEL and
>>>> XRD_LOGFILE envvars as described in the xrdcopy man page.
>>>
>>> Alja will run our test with this on ... but whatever the outcome,
>>> these connections should still be closed at some point.
>>>
>>> Andy, can you please comment on this? [Does anybody know, is Andy
>>> away ... or I should kick his chair in a separate email?]
>>>
>>> Cheers,
>>> Matevz
>>>
>>>> Cheers,
>>>> Lukasz
>>>>
>>>> On 23.08.2013 21:58, Fabrizio Furano wrote:
>>>>> Hi guys,
>>>>>
>>>>> you are reminding to me a historical thing with this thread. You
>>>>> may
>>>>> want to doublecheck these two points, and see if the defaults or the
>>>>> behavior is appropriate to the behavior of your proxy:
>>>>>
>>>>> - by choice the connections to the redirectors had a very long TTL,
>>>>> one day if I remember correctly
>>>>> - at some point, due to some interaction with the sec (don't
>>>>> remember
>>>>> exactly what by now) the behavior was changed to having one physical
>>>>> connection per process per user. Maybe Gerri remembers the
>>>>> rationale of
>>>>> this better than me. My point is to raise that if one sees many
>>>>> phyconns
>>>>> from the same process, they could be linked to different user ids.
>>>>> Worth
>>>>> checking IMHO.
>>>>>
>>>>> Hope that helps.
>>>>>
>>>>> Cheers
>>>>> Fabrizio
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> On 8/23/13 9:42 PM, Brian Bockelman wrote:
>>>>>> On Aug 23, 2013, at 2:05 PM, Alja Mrak Tadel
>>>>>> <[log in to unmask]> wrote:
>>>>>>
>>>>>>>>> normally XrdCl would open one connection per server it
>>>>>>>>> contacts.
>>>>>>>>> Not per file.
>>>>>>>>
>>>>>>>> OK, how do we get 105 connections from a single process to the
>>>>>>>> meta-manager then? :)
>>>>>>>
>>>>>>>
>>>>>>> FYI:: The connections listed with netstat are to the origin
>>>>>>> xrootd.unl.edu.
>>>>>>>
>>>>>>
>>>>>> Hi,
>>>>>>
>>>>>> So - we see duplicate connections to the redirector, but no
>>>>>> duplicate
>>>>>> connections to the data server?
>>>>>>
>>>>>> Could be a client bug, of course!
>>>>>>
>>>>>> Brian
>>>>>> ########################################################################
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>>>>>>
>>>>>
>>>>
>>>
>>
>
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