[rt-users] Slow Ticket History 3.8.8

Tue Sep 7 06:13:18 EDT 2010

Hi Justin,
just found this threat, sounds interessting.

What i read so far: You have 1 quad core system with 8GB RAM, running both
WEB and DB, correct?

Think you should follow Raed's hints first to log the queries generated with
RT

In terms of debug; if you have not done this yet enable DBIx-SearchBuilder
StatementLog
Set($StatementLog,’debug’);  in your etc/RT_SiteConfig.

I'm sure you will find some funny queries. Normally the Query Log of default
MySQL can only log queries taking longer than a second, but in your case i
think, you will have several much faster queries but in summary they take
longer - but you can't find in mysql-slow log.

Some more question regarding your hardware and setup.

1. One Server / quad core (hyper threating) -> how many threats for
Mysql/Postgresql? / 8 GB Ram
2. Hard Disk Setup? (logfiles and db storred on different HDD's? Any I/O
Problems?)
3. RT Rights Setup, does the user performance is faster or slower than the
performance with root user?

Some more information?

We're running also a larger RT Instance with dedicated hardware for DB and
Webservers with no huge perferomance bottlenacks.

Tob

2010/9/7 Justin Hayes <justin.hayes at openbet.com>

> I *think* we're just CPU bound. Roy's webservers are 3.6ghz so quite a bit
> faster than ours. We're going to try it on a faster server and that should
> drop our times. Guess we just wanted to explore all avenues before throwing
> hardware at the problem.
>
> Justin
>
> -------------------------------------------------
> Justin Hayes
> OpenBet Support Manager
> justin.hayes at openbet.com
>
> On 7 Sep 2010, at 10:30, Justin Hayes wrote:
>
> Tried Centos last night, and no difference at all.
>
> -------------------------------------------------
> Justin Hayes
> OpenBet Support Manager
> justin.hayes at openbet.com
>
> On 6 Sep 2010, at 20:49, Justin Hayes wrote:
>
> Hi Ruslan,
>
> Sorry looks like I shrunk the image too much. The thing I find odd is that
> there are others with similar hardware who don't get the problem. It'll be
> great if 3.10 fixes it for me, but I'd love to get to the bottom of it
> first. I'm pretty much positive it's not a DB issue, as I've tried different
> sizes of DB, tried postgres AND mysql etc. I don't think it's apache as I've
> tried the built in webserver with RT and no change there either.
>
> Currently trying to install RT on Centos given that Roy (who has kindly
> been helping me with details of his own setup) appears to have none of the
> same problems on that OS. Perhaps perl is just slow on the 64bit ubuntu
> we've currently got live.
>
> No idea if it's going to have any effect though :(
>
> Justin
>
> -------------------------------------------------
> Justin Hayes
> OpenBet Support Manager
> justin.hayes at openbet.com
>
> On 6 Sep 2010, at 18:37, Ruslan Zakirov wrote:
>
> Justin.
>
> First of all, I can not read from the chart, but anyway history rendering
> has been worked on in a new code branch. Probably this code will be part of
> RT 3.10. Code at the moment is unstable, but eventually it wil be faster
> then the current version.
>
> On Mon, Sep 6, 2010 at 8:56 PM, Justin Hayes <justin.hayes at openbet.com>wrote:
>
>> So far we've tried installing RT on different hardware, both 32 and 64bit
>> versions of linux. RT is still very slow for long tickets. All the time is
>> taken up by the perl/apache process maxing out a core of CPU.
>>
>> We've even gone as far as trying to profile the code. We came up with this
>> graph of where the time was going:
>>
>> <TIMING.png>
>> We then tried to go further into those functions but can't find a single
>> smoking gun call that is taking all the time.
>>
>> For example in a ticket that takes 22s to render approx 5 secs goes on
>> these 2 lines:
>>
>> File: Ticket/Elements/ShowHistory line: 100-103 version 3.8.8
>>
>> my @trans_attachments = grep { $_->TransactionId == $Transaction->Id }
>> @attachments;
>>
>> grep { ($_->TransactionId == $Transaction->Id ) &&
>> ($trans_content->{$_->Id} = $_)  } @attachment_content;
>>
>> Both are greps. Does this imply that perl itself is just slow?
>>
>> IF so why would our perl be slow compared to other people's? We've tried
>> compiling it from source and that made no difference.
>>
>> ATM we're at a bit of a loss....
>>
>> Justin
>>
>> -------------------------------------------------
>> Justin Hayes
>> OpenBet Support Manager
>> justin.hayes at openbet.com
>>
>> On 1 Jul 2010, at 11:51, Raed El-Hames wrote:
>>
>> Justin,
>>
>> Do you use Transaction custom fields, if you do n’t ; try and comment out
>> lines 70,71,72 from html/Ticket/Elements/ShowTransaction
>> % if ( $Transaction->CustomFieldValues->Count ) {
>>       <& /Elements/ShowCustomFields, Object => $Transaction &>
>> % }
>> See if that improves things for you.
>> Some of our monitoring tickets can have up to 500 updates, such tickets
>> use to take up to 20s to load, once I commented out the above lines, load
>> time is now down to less than 5 seconds.
>>
>> Regards;
>> Roy
>>
>>
>>  *From:* rt-users-bounces at lists.bestpractical.com [mailto:
>> rt-users-bounces at lists.bestpractical.com] *On Behalf Of *Justin Hayes
>>
>> *Sent:* 01 July 2010 11:39
>> *To:* Kenneth Crocker
>> *Cc:* rt-users at lists.bestpractical.com
>> *Subject:* Re: [rt-users] Slow Ticket History 3.8.8
>>
>> We do Kenneth, but most tickets don't have many file attachments, so I
>> assume that's not an issue?
>>
>> Cheers,
>>
>> Justin
>>
>> -------------------------------------------------
>> Justin Hayes
>> OpenBet Support Manager
>> justin.hayes at openbet.com
>>
>> On 29 Jun 2010, at 17:54, Kenneth Crocker wrote:
>>
>>
>> Justin,
>>
>> I didn't see this mentioned and may have missed it, but are you displaying
>> attachements inline? That might cut back on the I/O for History. Just a
>> thought.
>>
>> Kenn
>> LBNL
>> On Tue, Jun 29, 2010 at 8:04 AM, Justin Hayes <justin.hayes at openbet.com>
>> wrote:
>> As a test we've just created a long ticket in an empty RT DB and it's very
>> fast. So does look to be DB related - contrary to our earlier
>> investigations.
>>
>> I guess it must still access the DB resultset during the ticket rendering
>> (which isn't how we thought it would work).
>>
>> Time to tune the hell out of mysql then.......
>>
>>
>> Justin
>>
>> -------------------------------------------------
>> Justin Hayes
>> OpenBet Support Manager
>> justin.hayes at openbet.com
>> On 29 Jun 2010, at 15:53, Justin Hayes wrote:
>>
>> > Seem to be quite a few things to look at Jason. Need to figure out what
>> they all mean first.
>> >
>> > Justin
>> >
>> > -------- General Statistics
>> --------------------------------------------------
>> > [--] Skipped version check for MySQLTuner script
>> > [OK] Currently running supported MySQL version 5.1.37-1ubuntu5.4-log
>> > [OK] Operating on 64-bit architecture
>> >
>> > -------- Storage Engine Statistics
>> -------------------------------------------
>> > [--] Status: -Archive -BDB -Federated +InnoDB -ISAM -NDBCluster
>> > [--] Data in MyISAM tables: 611M (Tables: 8)
>> > [--] Data in InnoDB tables: 10G (Tables: 20)
>> > [!!] Total fragmented tables: 21
>> >
>> > -------- Performance Metrics
>> -------------------------------------------------
>> > [--] Up for: 19d 19h 32m 37s (110M q [64.266 qps], 222K conn, TX: 637B,
>> RX: 39B)
>> > [--] Reads / Writes: 98% / 2%
>> > [--] Total buffers: 602.0M global + 134.8M per thread (150 max threads)
>> > [!!] Maximum possible memory usage: 20.3G (262% of installed RAM)
>> > [OK] Slow queries: 0% (229K/110M)
>> > [!!] Highest connection usage: 100%  (151/150)
>> > [OK] Key buffer size / total MyISAM indexes: 512.0M/6.7M
>> > [OK] Key buffer hit rate: 100.0% (84M cached / 7K reads)
>> > [OK] Query cache efficiency: 71.4% (76M cached / 107M selects)
>> > [!!] Query cache prunes per day: 661360
>> > [OK] Sorts requiring temporary tables: 0% (0 temp sorts / 2M sorts)
>> > [!!] Joins performed without indexes: 112714
>> > [!!] Temporary tables created on disk: 33% (968K on disk / 2M total)
>> > [OK] Thread cache hit rate: 99% (1K created / 222K connections)
>> > [OK] Table cache hit rate: 36% (318 open / 880 opened)
>> > [OK] Open file limit used: 14% (166/1K)
>> > [OK] Table locks acquired immediately: 99% (39M immediate / 39M locks)
>> > [!!] InnoDB data size / buffer pool: 10.1G/8.0M
>> >
>> > -------- Recommendations
>> -----------------------------------------------------
>> > General recommendations:
>> >    Run OPTIMIZE TABLE to defragment tables for better performance
>> >    Reduce your overall MySQL memory footprint for system stability
>> >    Reduce or eliminate persistent connections to reduce connection usage
>> >    Adjust your join queries to always utilize indexes
>> >    When making adjustments, make tmp_table_size/max_heap_table_size
>> equal
>> >    Reduce your SELECT DISTINCT queries without LIMIT clauses
>> > Variables to adjust:
>> >  *** MySQL's maximum memory usage is dangerously high ***
>> >  *** Add RAM before increasing MySQL buffer variables ***
>> >    max_connections (> 150)
>> >    wait_timeout (< 28800)
>> >    interactive_timeout (< 28800)
>> >    query_cache_size (> 16M)
>> >    join_buffer_size (> 2.0M, or always use indexes with joins)
>> >    tmp_table_size (> 128M)
>> >    max_heap_table_size (> 64M)
>> >    innodb_buffer_pool_size (>= 10G)
>> >
>> >
>> > -------------------------------------------------
>> > Justin Hayes
>> > OpenBet Support Manager
>> > justin.hayes at openbet.com
>> >
>> > On 29 Jun 2010, at 15:22, Jason Doran wrote:
>> >
>> >> Hi,
>> >> If you are using mysqld have a look at "mysqltuner.pl" perl script
>> (google)
>> >> This has fixed quickly many performance issues on both RT and other
>> >> web-based software we use. I run this every few weeks and apply
>> suggested
>> >> changes and then simply restart mysqld when things are quite.
>> >>
>> >> Regards,
>> >> Jason Doran
>> >> Computer Centre
>> >> NUI, Maynooth
>> >>
>> >> On 29 Jun 2010, at 14:09, Justin Hayes wrote:
>> >>
>> >>> Hi everyone,
>> >>>
>> >>> I've raised this before, but we've had another look at it and still
>> can't see how to improve things.
>> >>>
>> >>> We put a lot of comments/replies in our tickets. Often there can be
>> 50-100 entries in a ticket, mostly plain text. Loading such a ticket can
>> take 10-20secs.
>> >>>
>> >>> We don't have any slow queries - all the time seems to be in the code
>> rendering the history of the ticket.
>> >>> We've had a go at stripping functions out of ShowHistory,
>> ShowTransaction and ShowTransactionAttachmments but not had much success.
>> >>>
>> >>> FWIW our RT runs on quad 3ghz Xeons with 8gb of ram.
>> >>>
>> >>> I'd like to try and determine if we're just slow, or if this is just
>> how long RT takes. Maybe perl is just slow.
>> >>>
>> >>> Can anyone shed any light on how long it takes them to render long
>> tickets in their systems? If you look at the page source it gives you a
>> value e.g.
>> >>>
>> >>> <span>Time to display: 24.996907</span>
>> >>>
>> >>> Can anyone share some numbers from theirs for longer tickets? It would
>> be really appreciated.
>> >>>
>> >>>
>> >>> Thanks,
>> >>>
>> >>> Justin
>> >>>
>> >>> -------------------------------------------------
>> >>> Justin Hayes
>> >>> OpenBet Support Manager
>> >>> justin.hayes at openbet.com
>> >>>
>> >>>
>> >>> Discover RT's hidden secrets with RT Essentials from O'Reilly Media.
>> >>> Buy a copy at http://rtbook.bestpractical.com
>> >>
>> >
>> >
>> > Discover RT's hidden secrets with RT Essentials from O'Reilly Media.
>> > Buy a copy at http://rtbook.bestpractical.com<http://rtbook.bestpracticalcom/>
>>
>>
>> Discover RT's hidden secrets with RT Essentials from O'Reilly Media.
>> Buy a copy at http://rtbook.bestpractical.com
>>
>>
>> Discover RT's hidden secrets with RT Essentials from O'Reilly Media.
>> Buy a copy at http://rtbook.bestpractical.com
>>
>>
>>
>>
>>
>> RT Training in Washington DC, USA on Oct 25 & 26 2010
>> Last one this year -- Learn how to get the most out of RT!
>>
>
>
>
> --
> Best regards, Ruslan.
>
>
>
> RT Training in Washington DC, USA on Oct 25 & 26 2010
> Last one this year -- Learn how to get the most out of RT!
>
>
>
> RT Training in Washington DC, USA on Oct 25 & 26 2010
> Last one this year -- Learn how to get the most out of RT!
>
>
>
>
> RT Training in Washington DC, USA on Oct 25 & 26 2010
> Last one this year -- Learn how to get the most out of RT!
>

-- 
MFG

Torsten Brumm

http://www.brumm.me
http://www.elektrofeld.de
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