{"id":484,"date":"2008-08-14T12:27:06","date_gmt":"2008-08-14T18:27:06","guid":{"rendered":"http:\/\/www.mooreds.com\/wordpress\/archives\/000484"},"modified":"2008-08-14T12:38:32","modified_gmt":"2008-08-14T18:38:32","slug":"mysql-and-memcached-notes-from-a-webinar","status":"publish","type":"post","link":"https:\/\/www.mooreds.com\/wordpress\/archives\/484","title":{"rendered":"MySQL and memcached: notes from a webinar"},"content":{"rendered":"

Just listened to another mysql webinar. This time it was about mysql and memcached. I got in a little late, but here are my notes.<\/p>\n

Memcached<\/a> is a distributed caching mechanism. Not as robust as Coherence<\/a>, for example, but free, open source, and widely used and supported.<\/p>\n

There is a project that hooks mysql UDFs to memecached<\/a>.<\/p>\n

The main speaker worked at Grazr<\/a>, a feed manipulation company. He presented some lessons and stated that some seemed obvious, but we all know how it is, you learn mistakes the hard way.<\/p>\n

    \n
  1. Beware architecture momentum–early decisions influence later ones.<\/li>\n
  2. Your scaling plan is wrong in some way!–grazr overbuilt.<\/li>\n
  3. Testing is limited: they had issues with replication speed. Users are better at testing site than any perl script.<\/li>\n
  4. Replication is fast, until it isn’t. It’s asynchronous nature can make it hard to program to.<\/li>\n
  5. Memcached is your friend<\/li>\n
  6. Sphinx<\/a>, an open source SQL full text search engine (like Lucene<\/a>), is your friend. It also has a mysql storage engine–virtual table that you can join with other data sources. This sounds cool.<\/li>\n
  7. Do bulk insert and lazy writes–if you don’t need to immediately read it, do the write later.<\/li>\n
  8. Emphasis on scaling hurt user experience. Fast, data correct transaction are available with two options: one server, or a sync buffer like memcached.<\/li>\n
  9. Use instrumentation–he mentioned tools like nagios<\/a> and cacti<\/a> (cacti has mysql plugin [which I couldn’t find]) to help scaling–close the loop: when you make a change, find out what that change did.<\/li>\n
  10. Try new things–for example, the MySQL blackhole storage engine<\/a> for data that is only read on slaves, not on the master.<\/li>\n
  11. Everyone has same problems–avoid Not Invented Here syndrome. Not just the obvious stuff (who writes a web server these days–oh wait<\/a>), for example, there’s a batch job processor like gearman. Note that he also said they had to Invent a few things before they learned this lesson.<\/li>\n
  12. Accept change–design for now+1, not now+100<\/li>\n
  13. Listen–even folks not intimately familiar with your technology may have good ideas, and more brains are better.<\/li>\n<\/ol>\n

    End notes<\/p>\n

    Looks like a couple of interesting whitepapers are available (you’ll have to register and get pinged via email a few times by sales folks): “Designing and Implementing Scalable Applications with Memcached and MySQL”<\/a>. And there are future webinars<\/a> on the MySQL\/memcached topic, one on SAAS applications and one on Scalable web architecture.<\/p>\n

    In a meta note, I enjoy the webinars because:<\/p>\n

      \n
    1. Easy to get to<\/li>\n
    2. Free<\/li>\n
    3. High quality<\/li>\n
    4. One can bail if you want (which I did a few weeks ago when MySQL proxy http:\/\/forge.mysql.com\/wiki\/MySQL_Proxy didn’t turn out to be all that interesting to me).<\/li>\n
    5. The give me something to blog about \ud83d\ude42<\/li>\n<\/ol>\n

      [tags]webinar, memcached, users are the best testers[\/tags]<\/p>\n","protected":false},"excerpt":{"rendered":"

      Just listened to another mysql webinar. This time it was about mysql and memcached. I got in a little late, but here are my notes. Memcached is a distributed caching […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[28],"tags":[],"class_list":["post-484","post","type-post","status-publish","format-standard","hentry","category-mysql"],"_links":{"self":[{"href":"https:\/\/www.mooreds.com\/wordpress\/wp-json\/wp\/v2\/posts\/484","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.mooreds.com\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.mooreds.com\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.mooreds.com\/wordpress\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.mooreds.com\/wordpress\/wp-json\/wp\/v2\/comments?post=484"}],"version-history":[{"count":0,"href":"https:\/\/www.mooreds.com\/wordpress\/wp-json\/wp\/v2\/posts\/484\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.mooreds.com\/wordpress\/wp-json\/wp\/v2\/media?parent=484"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.mooreds.com\/wordpress\/wp-json\/wp\/v2\/categories?post=484"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.mooreds.com\/wordpress\/wp-json\/wp\/v2\/tags?post=484"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}