Moses-support Digest, Vol 105, Issue 45

Send Moses-support mailing list submissions to
moses-support@mit.edu

To subscribe or unsubscribe via the World Wide Web, visit
http://mailman.mit.edu/mailman/listinfo/moses-support
or, via email, send a message with subject or body 'help' to
moses-support-request@mit.edu

You can reach the person managing the list at
moses-support-owner@mit.edu

When replying, please edit your Subject line so it is more specific
than "Re: Contents of Moses-support digest..."


Today's Topics:

1. Re: Performance issues using Moses Server with Moses 3 (Oren)
2. Performance issues using Moses Server with Moses 3 (Oren)


----------------------------------------------------------------------

Message: 1
Date: Tue, 21 Jul 2015 16:51:59 +0300
From: Oren <mooshified@gmail.com>
Subject: Re: [Moses-support] Performance issues using Moses Server
with Moses 3
To: Barry Haddow <bhaddow@staffmail.ed.ac.uk>
Cc: "moses-support@mit.edu" <moses-support@mit.edu>
Message-ID:
<CAHWEG_WV6nD4Fmj5tqrTkrMnHruSOjWHzicTmJxXYheD0pp0aw@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"

I am using the in-memory mode, using about 50GB of RAM. (No swap issues as
far as I can tell.) Could that cause issues?

I looked at the commit you linked to, but it doesn't seem to be something
configurable beyond the -threads switch. Am I missing something?

On Tuesday, July 21, 2015, Barry Haddow <bhaddow@staffmail.ed.ac.uk> wrote:

> Hi Oren
>
> Does your host have 18 threads available? It could also be that xmlrpc-c
> is limiting the number of connections - this can now be configured:
>
> https://github.com/moses-smt/mosesdecoder/commit/b3baade7f022edbcea2969679a40616683f63523
>
> Slowdowns in Moses are often caused by disk access bottlenecks. You can
> use --minphr-memory and --minlexr-memory to make sure that the phrase and
> reordering tables are loaded in to memory, rather than being access
> on-demand. Make sure your host has enough RAM and is not swapping. As I
> mentioned before there are various ways to make your models smaller (
> http://www.statmt.org/moses/?n=Advanced.RuleTables), which can make a big
> difference to speed depending on your setup.
>
> cheers - Barry
>
> On 21/07/15 09:30, Oren wrote:
>
> Hi Barry,
>
> Thanks for the quick response.
>
> I added the switch "-threads 18" to the command to raise moses server.
> The slowness issue persists but in a different form. Most requests return
> right away, even under heavy load, but some requests (about 5%) take far
> longer - about 15-20 seconds.
>
> Perhaps there are other relevant switches?
>
> Thanks again.
>
> On Monday, July 20, 2015, Barry Haddow <bhaddow@staffmail.ed.ac.uk
> <javascript:_e(%7B%7D,'cvml','bhaddow@staffmail.ed.ac.uk');>> wrote:
>
>> Hi Oren
>>
>> The threading model is different. In v1, the server created a new thread
>> for every request, v3 uses a thread pool. Try increasing the number of
>> threads.
>>
>> Also, make sure you use the compact phrase table and KenLM as they are
>> normally faster, and pre-pruning your phrase table can help,
>>
>> cheers - Barry
>>
>> On 20/07/15 12:01, Oren wrote:
>>
>> Hi all,
>>
>> We are in the process of migrating from Moses 1 to Moses 3. We have
>> noticed a significant slowdown when sending many requests at once to Moses
>> Server. The first request will actually finish about 25% faster that a
>> single request using Moses 1, but as more requests accumulate there is a
>> marked slowdown, until requests take 5 times longer or more.
>>
>> Is this a known issue? Is it specific to Moses Server? What can we do
>> about it?
>>
>> Thanks!
>>
>> Oren.
>>
>>
>> _______________________________________________
>> Moses-support mailing listMoses-support@mit.eduhttp://mailman.mit.edu/mailman/listinfo/moses-support
>>
>>
>>
>
> _______________________________________________
> Moses-support mailing listMoses-support@mit.edu <javascript:_e(%7B%7D,'cvml','Moses-support@mit.edu');>http://mailman.mit.edu/mailman/listinfo/moses-support
>
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mailman.mit.edu/mailman/private/moses-support/attachments/20150721/ab2a902c/attachment.htm

------------------------------

Message: 2
Date: Wed, 22 Jul 2015 17:09:28 +0300
From: Oren <mooshified@gmail.com>
Subject: [Moses-support] Performance issues using Moses Server with
Moses 3
To: Hieu Hoang <hieuhoang@gmail.com>
Cc: "moses-support@mit.edu" <moses-support@mit.edu>, Barry Haddow
<bhaddow@staffmail.ed.ac.uk>
Message-ID:
<CAHWEG_WaLjXds9PxS385_1QcugotD3P6wyatT=9z3O2aTGT0Hg@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"

We have no swapping issues. I was asking if the use of an in-memory
translation model might cause multithreading problems.


I'm not sure how to replicate the problem on cmd moses, since it's purely a
multithreading issue. Ca you run cmd moses multithreaded?

I can't attach the complete moses.ini because it's on a separate network...
But I copied below the stuff that looked relevant. I also tried to change
the [threads] setting to 18, with no apparent effect.

[input-factors]
0

[mapping]
0 T 0

[distortion-limit]
6

[feature]
UnknownWordPenalty
WordPenalty
PhrasePenalty
PhraseDictionaryMemory name=TranslationModel0 num-features=4
path=<path>/phrase-table.gz input-factor=0 output-factor=0
LexicalReordering <parameters>
Distortion
KENLM lazyken=0 name=LM0 path=<path> order=5

[threads]
6

[weight]

<weight parameters>

On Tuesday, July 21, 2015, Hieu Hoang <hieuhoang@gmail.com
<javascript:_e(%7B%7D,'cvml','hieuhoang@gmail.com');>> wrote:

> is it possible you can make your moses.ini file available for us to see?
>
> do you know if the same problem occurs if you use the command line moses,
> rather than mosesserver?
>
>
> Hieu Hoang
> Researcher
> New York University, Abu Dhabi
> http://www.hoang.co.uk/hieu
>
> On 21 July 2015 at 18:07, Barry Haddow <bhaddow@staffmail.ed.ac.uk> wrote:
>
>>
>> On 21/07/15 14:51, Oren wrote:
>>
>> I am using the in-memory mode, using about 50GB of RAM. (No swap issues
>> as far as I can tell.) Could that cause issues?
>>
>>
>> Yes, swapping would definitely cause issues - was that your question?
>>
>>
>>
>> I looked at the commit you linked to, but it doesn't seem to be
>> something configurable beyond the -threads switch. Am I missing something?
>>
>>
>> The commit enables you to set the maximum number of connections to be the
>> same as the maximum number of threads.
>>
>>
>> On Tuesday, July 21, 2015, Barry Haddow <bhaddow@staffmail.ed.ac.uk>
>> wrote:
>>
>>> Hi Oren
>>>
>>> Does your host have 18 threads available? It could also be that xmlrpc-c
>>> is limiting the number of connections - this can now be configured:
>>>
>>> https://github.com/moses-smt/mosesdecoder/commit/b3baade7f022edbcea2969679a40616683f63523
>>>
>>> Slowdowns in Moses are often caused by disk access bottlenecks. You can
>>> use --minphr-memory and --minlexr-memory to make sure that the phrase and
>>> reordering tables are loaded in to memory, rather than being access
>>> on-demand. Make sure your host has enough RAM and is not swapping. As I
>>> mentioned before there are various ways to make your models smaller (
>>> http://www.statmt.org/moses/?n=Advanced.RuleTables), which can make a
>>> big difference to speed depending on your setup.
>>>
>>> cheers - Barry
>>>
>>> On 21/07/15 09:30, Oren wrote:
>>>
>>> Hi Barry,
>>>
>>> Thanks for the quick response.
>>>
>>> I added the switch "-threads 18" to the command to raise moses server.
>>> The slowness issue persists but in a different form. Most requests return
>>> right away, even under heavy load, but some requests (about 5%) take far
>>> longer - about 15-20 seconds.
>>>
>>> Perhaps there are other relevant switches?
>>>
>>> Thanks again.
>>>
>>> On Monday, July 20, 2015, Barry Haddow <bhaddow@staffmail.ed.ac.uk>
>>> wrote:
>>>
>>>> Hi Oren
>>>>
>>>> The threading model is different. In v1, the server created a new
>>>> thread for every request, v3 uses a thread pool. Try increasing the number
>>>> of threads.
>>>>
>>>> Also, make sure you use the compact phrase table and KenLM as they are
>>>> normally faster, and pre-pruning your phrase table can help,
>>>>
>>>> cheers - Barry
>>>>
>>>> On 20/07/15 12:01, Oren wrote:
>>>>
>>>> Hi all,
>>>>
>>>> We are in the process of migrating from Moses 1 to Moses 3. We have
>>>> noticed a significant slowdown when sending many requests at once to Moses
>>>> Server. The first request will actually finish about 25% faster that a
>>>> single request using Moses 1, but as more requests accumulate there is a
>>>> marked slowdown, until requests take 5 times longer or more.
>>>>
>>>> Is this a known issue? Is it specific to Moses Server? What can we do
>>>> about it?
>>>>
>>>> Thanks!
>>>>
>>>> Oren.
>>>>
>>>>
>>>> _______________________________________________
>>>> Moses-support mailing listMoses-support@mit.eduhttp://mailman.mit.edu/mailman/listinfo/moses-support
>>>>
>>>>
>>>>
>>>
>>> _______________________________________________
>>> Moses-support mailing listMoses-support@mit.eduhttp://mailman.mit.edu/mailman/listinfo/moses-support
>>>
>>>
>>>
>>
>> The University of Edinburgh is a charitable body, registered in
>> Scotland, with registration number SC005336.
>>
>> _______________________________________________
>> Moses-support mailing list
>> Moses-support@mit.edu
>> http://mailman.mit.edu/mailman/listinfo/moses-support
>>
>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mailman.mit.edu/mailman/private/moses-support/attachments/20150722/215d8105/attachment.htm

------------------------------

_______________________________________________
Moses-support mailing list
Moses-support@mit.edu
http://mailman.mit.edu/mailman/listinfo/moses-support


End of Moses-support Digest, Vol 105, Issue 45
**********************************************

Tweet