… at mk-query-digest report we typically look at the Queries causing the most impact (sum of the query execution times) as well as queries having… data for the all server – understanding what queries are being ran (together with other interactions – memcache, remote sites etc) is a key…
Post: Maatkit Now Supports Memcached
July 24, 2009 By 11 Comments
…’s how: Get the latest mk-query-digest Capture memcached network traffic with tcpdump Parse memcached network traffic with mk-query-digest Ponder the results, or consider a…/svn/trunk/mk-query-digest/mk-query-digest sudo tcpdump -s 65535 -x -n -q -tttt -i eth0 port 11211 > memc_tcpdump.txt mk-query-digest –type memcached memc_tcpdump…
Comment: Maatkit Now Supports Memcached
July 24, 2009 By 11 Comments
I have root@lb2:~# ./mk-query-digest –type memcached memc_tcpdump.txt # mk_query_digest:6381 6920 Use of uninitialized value in string eq at ./mk-query-digest line 5363, chunk 1. # # mk_query_digest:6381 6920 Use of uninitialized value in string eq at ./mk-query-digest line 5363, chunk 2. #
Comment: Maatkit Now Supports Memcached
July 30, 2009 By 11 Comments
When I try to use it, it just gives lots of these lines: ./mk-query-digest –type memcached memc_tcpdump.txt # mk_query_digest:6758 5136 tell() on closed filehandle at ./mk-query-digest line 2019.
Comment: How to Identify Bad Queries in MySQL
January 11, 2011 By 16 Comments
… the database server” to “it’s the RAID controller” to memcached, the load balancer, the switch, the network, the connection pool… wrote mk-query-digest, so I certainly understand your points, and they are good — my intent with this article was to show where mk-query-digest…’t so good, you wouldn’t say that finding bad queries is “the easy part.”
Post: Cache Miss Storm
September 10, 2010 By 30 Comments
… the same query with same constants. What we observed was a cache miss storm – situation which can happen with memcache (as in this case) as well as with query cache. If you have the item… find first one for memcached you can use mk-query-digest to analyze which items are requested frequently, it can decode memcached wire traffic. For…
Comment: How to Identify Bad Queries in MySQL
January 11, 2011 By 16 Comments
… say that finding bad queries is “the easy part.— I can agree with that, and mk-query-digest is an excellent tool… slowlogs. For SQL tuning, I check the top-sql as query-digest shows. Check the plan and indexes involved. I want to… database server†to “it’s the RAID controller†to memcached, the load balancer, the switch, the network, the connection pool…
Comment: Maatkit Now Supports Memcached
May 29, 2012 By 11 Comments
Nice post. I want to add that if you run memcached server on a non-11211 port, you need to add –watch-server to mk-query-digest or you will get “Packet is not to or from memcached server” error.
Post: Caching could be the last thing you want to do
July 24, 2010 By 14 Comments
… clearly they weren’t). I think with great tools like memcached it is easy to get carried away and use it… execution plan of every query? If you don’t, set long_query_time=0 and use mk-query-digest to capture queries. Run them through MySQL’s EXPLAIN command. Do your queries SELECT *, only…
Comment: Caching could be the last thing you want to do
July 25, 2010 By 14 Comments
… — using memcached is far less work than doing the methodical (and boring) work of optimizing each and every single query that is actually used. mk-query-digest is an awesome tool — I use it to do query reviews for clients…
