…normal;overflow:hidden;text-indent:0px;padding-left:3px;border-top:1px solid #CCC;border-right:1px solid #CCC;border-bottom…9 year35.9046.2052.8482.73935.9037091732036.20541715621952.84753513336182.7391619682312.10 year40.567.0243.0623.10140.5600171089177.02445888519293.06234693527223.1008150577545….
Post: Identifying the load with the help of pt-query-digest and Percona Server
December 29, 2011 By 3 Comments
….8137 10.0% 3853 0.0002 NS 0.0 The above part of the output ranks the queries and shows the top…” is not covered by top queries, we have 10% in MISC which means that by reviewing these top 20 queries we essentially reviewed… # Query_time distribution # 1us # 10us # 100us ################### # 1ms ################################################################ # 10ms # # 100ms # 1s # 10s+ # Tables # SHOW TABLE STATUS FROM `wp_blog_one ` LIKE ‘wp…
Post: Aligning IO on a hard disk RAID – the Benchmarks
June 9, 2011 By 13 Comments
… irrelevant information): # Aspersa System Summary Report ############################## Platform | Linux Release | Ubuntu 10.04.2 LTS (lucid) Kernel | 2.6.32-31-server… slightly over 1TB in size. When I added LVM on top however, I made the logical volume slightly below 1TB. Investigating… able to fix that (not verified). 6. Added LVM on top of aligned partition table, used proper file system alignment. Benchmark…
Post: Using GROUP BY WITH ROLLUP for Reporting Performance Optimization
September 17, 2007 By 14 Comments
Quite typical query for reporting applications is to find top X values. If you analyze Web Site logs you would … reporting you may be interested in best selling product or top sales people. This information may often need simple select query… like “a%” group by grp order by cnt desc limit 10; +——+—–+ | grp | cnt | +——+—–+ | 9879 | 300 | | 3888 | 298 | | 1793 | 297 | | 2082 | 294…
Post: Goal driven performance optimization
December 22, 2008 By Leave a Comment
… 45.388828675971 | 0.9226436892381 | | 09 | 4810 | 6.330725168364 | 0.60329631087965 | | 10 | 5445 | 3.8355732669953 | 0.53918653169648 | | 11 | 5283 | 3.0498331333457 |… it affects Sphinx layer significantly. Such goal based from top to bottom approach is especially helpful for complex applications …
Comment: Full text search for all MySQL Storage Engines
June 29, 2006 By 37 Comments
… relevance. If you sort by relevance and pick up say top 200 hits you will most likely miss newer posts which… result to be top 200 sorted by date. For mysql fulltext that means that if each of the 10 common words produces… me why mysqls fulltext takes more than 800seconds for this 10 most common word case 
), fill it with the internal…
Post: ORDER BY ... LIMIT Performance Optimization
September 1, 2006 By 100 Comments
… sets being sorted. On many web sites you will fine top tags, recently registered users etc – which would often require ORDER… category large portion of table may be scanned to find 10 rows. So index on (category_id, date_created) will be… them for positions. So instead of query with LIMIT 1000,10 you will have WHERE position between 1000 and 1009 which…
Comment: Full text search for all MySQL Storage Engines
June 29, 2006 By 37 Comments
… results: 10 most common words along with -b -l 200 –sort=date (in boolean mode sorting by date descending returning top 200…_match: 8.76, self: 6.60 read_hits: 2.16 ————— 10 most common words along with only -l 200 –sort=date… search available in sphinx, defaulting to SPH_MATCH_ALL) returning top 200 matches): — PROFILE — root: 12.86, self: 0.00 query…
Post: Some fun with R visualization
February 23, 2012 By 5 Comments
… measurements. I run benchmark for 1 hours, with measurements every 10 seconds. So we have 360 points – metrics. If we draw…
Post: 3 ways MySQL uses indexes
September 12, 2009 By 28 Comments
… able to help lookup rows for B BETWEEN 5 AND 10 predicate because it is not index prefix. It is important… for row lookups and scan whole A BETWEEN 5 AND 10 range. It is interesting to note this limitation only applies… across many pages requiring potentially a lot of IOs. On top of that if you just need access to couple of…
