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From:Michael Dykman Date:October 6 2011 5:00pm
Subject:Re: 4 minute slow on select count(*) from table - myisam type
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I am curious..  Are you the only client on this database or or there other
connections doing work in the background?  A busy insert/update heavy
application could cause these effects.

 - michael dykman

On Thu, Oct 6, 2011 at 12:35 PM, Joey L <mjh2000@stripped> wrote:

> i did google search - myisam is faster...i am not really doing any
> transaction stuff.
> thanks
>
> On Thu, Oct 6, 2011 at 12:16 PM, Andrew Moore <eroomydna@stripped> wrote:
> > Sorry, hit send by accident there! *face palm*
> > Just had a quick scan of the report. You've got 2 1GB disks in software
> raid
> > - RAID1 or RAID5? I can also see you're creating a lot of temporary files
> on
> > disk. I think in your previous email that your biggest table's index(s)
> were
> > larger then the keybuffer size. I would suspect that you're disk bound
> with
> > limited IO performance through 2 disks and effectively 1 if in a mirrored
> > configuration. The stats show that you're configured for MyISAM and that
> > you're tables are taking reads and writes (read heavy though), MyISAM
> > doesn't like high concurrency mixed workloads such as yours, it will
> cause
> > locking and maybe thats why your count has such a delay. Such activity
> may
> > be better suited to InnoDB engine (you must configure and tune for this,
> not
> > JUST change the engine).
> > HTH
> > Andy
> >
> >
> > On Thu, Oct 6, 2011 at 5:05 PM, Andrew Moore <eroomydna@stripped>
> wrote:
> >>
> >> Joey, does your 'large' table get
> >>
> >> On Thu, Oct 6, 2011 at 3:22 PM, Joey L <mjh2000@stripped> wrote:
> >>>
> >>> here is mysqlreport ---
> >>> ------------------------------------------------
> >>> root@rider:~/tmp# ./mysqlreport --user root --password barakobomb
> >>> Use of uninitialized value $is in multiplication (*) at ./mysqlreport
> >>> line 829.
> >>> Use of uninitialized value in formline at ./mysqlreport line 1227.
> >>> MySQL 5.1.49-3-log       uptime 0 0:25:5        Thu Oct  6 10:20:49
> 2011
> >>>
> >>> __ Key
> _________________________________________________________________
> >>> Buffer used   727.43M of   2.00G  %Used:  35.52
> >>>  Current     963.24M            %Usage:  47.03
> >>> Write hit      29.41%
> >>> Read hit       99.79%
> >>>
> >>> __ Questions
> ___________________________________________________________
> >>> Total          50.20k    33.4/s
> >>>  QC Hits      32.56k    21.6/s  %Total:  64.87
> >>>  DMS          12.28k     8.2/s           24.46
> >>>  Com_          3.21k     2.1/s            6.39
> >>>  COM_QUIT      2.89k     1.9/s            5.76
> >>>  -Unknown        745     0.5/s            1.48
> >>> Slow 10 s          68     0.0/s            0.14  %DMS:   0.55  Log: OFF
> >>> DMS            12.28k     8.2/s           24.46
> >>>  SELECT       11.09k     7.4/s           22.10         90.36
> >>>  UPDATE          539     0.4/s            1.07          4.39
> >>>  INSERT          384     0.3/s            0.77          3.13
> >>>  DELETE          260     0.2/s            0.52          2.12
> >>>  REPLACE           0       0/s            0.00          0.00
> >>> Com_            3.21k     2.1/s            6.39
> >>>  set_option    1.10k     0.7/s            2.20
> >>>  show_fields   1.03k     0.7/s            2.05
> >>>  admin_comma     707     0.5/s            1.41
> >>>
> >>> __ SELECT and Sort
> _____________________________________________________
> >>> Scan            1.65k     1.1/s %SELECT:  14.87
> >>> Range             493     0.3/s            4.44
> >>> Full join         310     0.2/s            2.79
> >>> Range check       339     0.2/s            3.06
> >>> Full rng join       0       0/s            0.00
> >>> Sort scan         887     0.6/s
> >>> Sort range        628     0.4/s
> >>> Sort mrg pass       0       0/s
> >>>
> >>> __ Query Cache
> _________________________________________________________
> >>> Memory usage    5.96M of  16.00M  %Used:  37.25
> >>> Block Fragmnt   5.17%
> >>> Hits           32.56k    21.6/s
> >>> Inserts         5.66k     3.8/s
> >>> Insrt:Prune   5.66k:1     3.8/s
> >>> Hit:Insert     5.76:1
> >>>
> >>> __ Table Locks
> _________________________________________________________
> >>> Waited            513     0.3/s  %Total:   3.62
> >>> Immediate      13.65k     9.1/s
> >>>
> >>> __ Tables
> ______________________________________________________________
> >>> Open             1024 of 1024    %Cache: 100.00
> >>> Opened         14.96k     9.9/s
> >>>
> >>> __ Connections
> _________________________________________________________
> >>> Max used           70 of  100      %Max:  70.00
> >>> Total           2.89k     1.9/s
> >>>
> >>> __ Created Temp
> ________________________________________________________
> >>> Disk table      1.34k     0.9/s
> >>> Table           2.35k     1.6/s    Size:  32.0M
> >>> File                5     0.0/s
> >>>
> >>> __ Threads
> _____________________________________________________________
> >>> Running            32 of   37
> >>> Cached              0 of    8      %Hit:  93.26
> >>> Created           195     0.1/s
> >>> Slow                0       0/s
> >>>
> >>> __ Aborted
> _____________________________________________________________
> >>> Clients             0       0/s
> >>> Connects            2     0.0/s
> >>>
> >>> __ Bytes
> _______________________________________________________________
> >>> Sent          100.33M   66.7k/s
> >>> Received       12.48M    8.3k/s
> >>>
> >>> __ InnoDB Buffer Pool
> __________________________________________________
> >>> Usage           1.67M of   8.00M  %Used:  20.90
> >>> Read hit       99.70%
> >>> Pages
> >>>  Free            405            %Total:  79.10
> >>>  Data            107                     20.90 %Drty:   0.00
> >>>  Misc              0                      0.00
> >>>  Latched                                  0.00
> >>> Reads          26.18k    17.4/s
> >>>  From file        78     0.1/s            0.30
> >>>  Ahead Rnd         2     0.0/s
> >>>  Ahead Sql         1     0.0/s
> >>> Writes              3     0.0/s
> >>> Flushes             3     0.0/s
> >>> Wait Free           0       0/s
> >>>
> >>> __ InnoDB Lock
> _________________________________________________________
> >>> Waits               0       0/s
> >>> Current             0
> >>> Time acquiring
> >>>  Total             0 ms
> >>>  Average           0 ms
> >>>  Max               0 ms
> >>>
> >>> __ InnoDB Data, Pages, Rows
> ____________________________________________
> >>> Data
> >>>  Reads            96     0.1/s
> >>>  Writes           12     0.0/s
> >>>  fsync            11     0.0/s
> >>>  Pending
> >>>    Reads           0
> >>>    Writes          0
> >>>    fsync           0
> >>>
> >>> Pages
> >>>  Created           0       0/s
> >>>  Read            107     0.1/s
> >>>  Written           3     0.0/s
> >>>
> >>> Rows
> >>>  Deleted           0       0/s
> >>>  Inserted          0       0/s
> >>>  Read         20.98k    13.9/s
> >>>  Updated           0       0/s
> >>> root@rider:~/tmp#
> >>>
> >>> and the mysqltuner.pl report :
> >>> -------------------------------------------------------------
> >>>
> >>> root@rider:~/tmp# perl mysqltuner.pl
> >>>
> >>>  >>  MySQLTuner 1.2.0 - Major Hayden <major@stripped>
> >>>  >>  Bug reports, feature requests, and downloads at
> >>> http://mysqltuner.com/
> >>>  >>  Run with '--help' for additional options and output
> filtering
> >>> Please enter your MySQL administrative login: root
> >>> Please enter your MySQL administrative password:
> >>>
> >>> -------- General Statistics
> >>> --------------------------------------------------
> >>> [--] Skipped version check for MySQLTuner script
> >>> [OK] Currently running supported MySQL version 5.1.49-3-log
> >>> [OK] Operating on 64-bit architecture
> >>>
> >>> -------- Storage Engine Statistics
> >>> -------------------------------------------
> >>> [--] Status: +Archive -BDB -Federated +InnoDB -ISAM -NDBCluster
> >>> [--] Data in MyISAM tables: 7G (Tables: 2408)
> >>> [--] Data in InnoDB tables: 1M (Tables: 37)
> >>> [!!] Total fragmented tables: 49
> >>>
> >>> -------- Security Recommendations
> >>>  -------------------------------------------
> >>> [OK] All database users have passwords assigned
> >>>
> >>> -------- Performance Metrics
> >>> -------------------------------------------------
> >>> [--] Up for: 26m 26s (54K q [34.593 qps], 2K conn, TX: 110M, RX: 13M)
> >>> [--] Reads / Writes: 90% / 10%
> >>> [--] Total buffers: 2.1G global + 2.6M per thread (100 max threads)
> >>> [OK] Maximum possible memory usage: 2.3G (19% of installed RAM)
> >>> [OK] Slow queries: 0% (69/54K)
> >>> [OK] Highest usage of available connections: 70% (70/100)
> >>> [OK] Key buffer size / total MyISAM indexes: 2.0G/9.2G
> >>> [OK] Key buffer hit rate: 99.8% (363M cached / 745K reads)
> >>> [OK] Query cache efficiency: 76.1% (36K cached / 47K selects)
> >>> [OK] Query cache prunes per day: 0
> >>> [OK] Sorts requiring temporary tables: 0% (0 temp sorts / 1K sorts)
> >>> [!!] Joins performed without indexes: 689
> >>> [!!] Temporary tables created on disk: 36% (1K on disk / 4K total)
> >>> [OK] Thread cache hit rate: 93% (198 created / 2K connections)
> >>> [!!] Table cache hit rate: 6% (1K open / 14K opened)
> >>> [!!] Open file limit used: 89% (1K/2K)
> >>> [OK] Table locks acquired immediately: 96% (14K immediate / 14K locks)
> >>> [OK] InnoDB data size / buffer pool: 1.2M/8.0M
> >>>
> >>> -------- Recommendations
> >>> -----------------------------------------------------
> >>> General recommendations:
> >>>    Run OPTIMIZE TABLE to defragment tables for better performance
> >>>    MySQL started within last 24 hours - recommendations may be
> inaccurate
> >>>    Enable the slow query log to troubleshoot bad queries
> >>>    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
> >>>    Increase table_cache gradually to avoid file descriptor limits
> >>> Variables to adjust:
> >>>    join_buffer_size (> 8.0K, or always use indexes with joins)
> >>>    tmp_table_size (> 32M)
> >>>    max_heap_table_size (> 32M)
> >>>    table_cache (> 1024)
> >>>    open_files_limit (> 2158)
> >>>
> >>> root@rider:~/tmp#
> >>>
> >>>
> >>>
> >>> On Thu, Oct 6, 2011 at 10:09 AM, Rik Wasmus <rik@stripped> wrote:
> >>> >> thanks for the response - but do not believe queries are the
> issue
> >>> >> because - Like I said - i have other websites doing the same
> exact
> >>> >> queries as I am doing on the site with the 9gig table.
> >>> >
> >>> > Contrary to popular believe, size DOES matter... And having a
> table
> >>> > large
> >>> > enough so it doesn't fit in memory could require another approach
> >>> > entirely for
> >>> > query optimization.
> >>> >
> >>> > Another good start would be to examine the output of mysqlreport,
> it
> >>> > will tel
> >>> > you a lot.
> >>> > --
> >>> > Rik Wasmus
> >>> >
> >>> > --
> >>> > MySQL General Mailing List
> >>> > For list archives: http://lists.mysql.com/mysql
> >>> > To unsubscribe:
> http://lists.mysql.com/mysql?unsub=1
> >>> >
> >>> >
> >>>
> >>> --
> >>> MySQL General Mailing List
> >>> For list archives: http://lists.mysql.com/mysql
> >>> To unsubscribe:
> http://lists.mysql.com/mysql?unsub=1
> >>>
> >>
> >
> >
>
> --
> MySQL General Mailing List
> For list archives: http://lists.mysql.com/mysql
> To unsubscribe:    http://lists.mysql.com/mysql?unsub=1
>
>


-- 
 - michael dykman
 - mdykman@stripped

 May the Source be with you.

Thread
4 minute slow on select count(*) from table - myisam typeJoey L2 Oct
  • Re: 4 minute slow on select count(*) from table - myisam typeAndrew Moore2 Oct
    • Re: 4 minute slow on select count(*) from table - myisam typeJoey L2 Oct
  • Re: 4 minute slow on select count(*) from table - myisam typeBruce Ferrell2 Oct
Re: 4 minute slow on select count(*) from table - myisam typeAndrew Moore2 Oct
  • Re: 4 minute slow on select count(*) from table - myisam typeJoey L3 Oct
    • Re: 4 minute slow on select count(*) from table - myisam typeJoey L3 Oct
      • Re: 4 minute slow on select count(*) from table - myisam typeBruce Ferrell3 Oct
        • Re: 4 minute slow on select count(*) from table - myisam typeJoey L3 Oct
          • Re: 4 minute slow on select count(*) from table - myisam typeAndrĂ©s Tello3 Oct
            • Re: 4 minute slow on select count(*) from table - myisam typeJoey L3 Oct
              • Re: 4 minute slow on select count(*) from table - myisam typeEric Bergen3 Oct
                • Re: 4 minute slow on select count(*) from table - myisam typeJoey L6 Oct
                  • Re: 4 minute slow on select count(*) from table - myisam typeJoey L6 Oct
                    • Re: 4 minute slow on select count(*) from table - myisam typeJohnny Withers6 Oct
                      • Re: 4 minute slow on select count(*) from table - myisam typeJoey L6 Oct
                        • Re: 4 minute slow on select count(*) from table - myisam typeJohnny Withers6 Oct
                        • Re: 4 minute slow on select count(*) from table - myisam typeJohan De Meersman6 Oct
                        • Re: 4 minute slow on select count(*) from table - myisam typeRik Wasmus6 Oct
                          • Re: 4 minute slow on select count(*) from table - myisam typeJoey L6 Oct
                            • Re: 4 minute slow on select count(*) from table - myisam typeAndrew Moore6 Oct
                              • Re: 4 minute slow on select count(*) from table - myisam typeAndrew Moore6 Oct
                                • Re: 4 minute slow on select count(*) from table - myisam typeJoey L6 Oct
                                  • Re: 4 minute slow on select count(*) from table - myisam typeMichael Dykman6 Oct
Re: 4 minute slow on select count(*) from table - myisam typeAndrew Moore6 Oct
  • Re: 4 minute slow on select count(*) from table - myisam typeJoey L6 Oct
Re: 4 minute slow on select count(*) from table - myisam typeJohnny Withers6 Oct
  • Re: 4 minute slow on select count(*) from table - myisam typeJohan De Meersman7 Oct
Re: 4 minute slow on select count(*) from table - myisam typeJan Steinman7 Oct
  • Re: 4 minute slow on select count(*) from table - myisam typeJoey L7 Oct
    • Re: 4 minute slow on select count(*) from table - myisam typeAndrew Moore7 Oct