incubator-couchdb-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Jason Smith <...@iriscouch.com>
Subject Re: how to debug a single PUT that is very slow?
Date Mon, 02 Apr 2012 07:49:32 GMT
Hi, Mark. How is your command line-fu?

It would be interesting to see how many `couchjs` processes your
`beam` (or `beam.smp`) process has spawned.

How does that compare with your CouchDB configuration,
/_config/query_server_config/os_process_limit?

On Mon, Apr 2, 2012 at 7:28 AM, Mark Hahn <mark@hahnca.com> wrote:
>>  Do you have a validate_doc_update function in any design documents in
> that database?
>
> No, just an update handler and a few filters.  I use the update handler a
> lot, almost every PUT.  I rarely PUT an entire doc except when creating a
> new one, as in this situation.
>
> Interesting.  I'm having a problem while lots of update handlers are
> running.  I wonder if this is a significant clue.
>
> On Mon, Apr 2, 2012 at 12:02 AM, Jason Smith <jhs@iriscouch.com> wrote:
>
>> Hi, Mark. Do you have a validate_doc_update function in any design
>> documents in that database?
>>
>> Thanks.
>>
>> On Mon, Apr 2, 2012 at 1:41 PM, Mark Hahn <mark@hahnca.com> wrote:
>> > I'm having a problem in a particular situation where a specific put of a
>> > new document is taking 10 to 20 seconds.  The db is not very loaded down.
>> >  There are 5 to 25 writes/sec and about 200 reads per second.  I have a
>> db
>> > watcher that is invoked on every change.
>> >
>> > Looking at the log timestamps, the PUT for the new document doesn't even
>> > register as an [info] line until ten seconds after my app sent the http
>> > request.  The log just shows normal read and writes during that 10
>> seconds.
>> >  No view is being rebuilt nor is there a compaction happening.
>> >
>> > I can repeat this any time I want by uploading 18 files from my browser,
>> > where each of the 18 triggers an invocation of imagemagick thumbnail
>> > conversion and then adding that thumbnail as an attachment to each of 18
>> > docs.  The attachments are only about 20 kbytes each.  The doc that is
>> > trying to be created is unrelated to any of those 18.  The problem just
>> > happens when I try to create the doc at the same time.
>> >
>> > The cpu is not loaded.  Node and the db are only consuming about 15% each
>> > of the cpu during the episode.
>> >
>> > Any idea what could cause this?  What can I do to track the problem down?
>>
>>
>>
>> --
>> Iris Couch
>>



-- 
Iris Couch

Mime
View raw message