Oct 07, 2011 |
MySQL
At next week’s NY Effective MySQL Meetup, I will give a talk: “Understanding Indexing: Three rules on making indexes around queries to provide good performance.” The meetup is 7 pm Tuesday, October 11th, and will be held at Hive at 55 (55 Broad Street, New York, NY). Thanks to host Ronald Bradford for the invitation. […]
Jul 15, 2011 |
MySQL
Thanks again to Erin O’Neill and Mike Tougeron for having me at the SF MySQL Meetup last month for the talk on “Understanding Indexing.” The crowd was very interactive, and I appreciated that over 100 people signed up for the event and left some very positive comments and reviews. Thanks to Mike, a video of […]
Jun 21, 2011 |
MySQL
At this week’s SF MySQL Meetup, I will give a talk: “Understanding Indexing: Three rules on making indexes around queries to provide good performance.” The meetup is 7 pm tomorrow (Wednesday, 6/22), and will be held at CBS Interactive (235 2nd St., San Francisco). Thanks to hosts Erin O’Neill and Mike Tougeron for the invitation […]
Apr 26, 2011 |
MySQL
Kudos to Ronald Bradford for creating a new MySQL meetup group in New York city and giving MySQL related talks. The next one is tonight, titled “MySQL Idiosyncrasies That Bite”. Information on it can be found at http://ny.effectivemysql.com/events/16884850/. We’ll have a contingent from our New York office there this evening. We went to the last […]
Mar 16, 2011 |
MySQL
Yesterday, at the Boston MySQL Meetup, I gave a talk on indexing. It is posted here (also goo.gl/S2LBe). In short, indexes are used to improve query performance. As a result, good indexes are designed around queries that users find important in their application. The presentation covers three simple and effective rules on how to construct […]
Sep 16, 2010 |
MySQL
TokuDB’s loader uses the available multicore computing resources of the machine to presort and insert the data. In the last couple of posts (here and here), Rich and Dave presented performance results of TokuDB’s loader. Comparing load times with TokuDB 2.1.0, Rich found a 2.1x speedup on a 2 core machine, and a 4.2x speedup […]
Aug 11, 2010 |
MySQL
In posts on June 30 and July 6, I explained how implementing the commands “replace into” and “insert ignore” with TokuDB’s fractal trees data structures can be two orders of magnitude faster than implementing them with B-trees. Towards the end of each post, I hinted at that there are some caveats that complicate the story […]
Jul 21, 2010 |
MySQL
In posts on June 30 and July 6, I explained how implementing the commands “replace into” and “insert ignore” with TokuDB’s fractal trees data structures can be two orders of magnitude faster than implementing them with B-trees. Towards the end of each post, I hinted at that there are some caveats that complicate the story […]
Jul 14, 2010 |
MySQL
In my post on June 18th, I explained why the semantics of normal ad-hoc insertions with a primary key are expensive because they require disk seeks on large data sets. I previously explained why it would be better to use “replace into” or to use “insert ignore” over normal inserts. In this post, I explain […]
Jul 06, 2010 |
MySQL
In my post from three weeks ago, I explained why the semantics of normal ad-hoc insertions with a primary key are expensive because they require disk seeks on large data sets. Towards the end of the post, I claimed that it would be better to use “replace into” or “insert ignore” over normal inserts, because […]
Jun 30, 2010 |
MySQL
In this post two weeks ago, I explained why the semantics of normal ad-hoc insertions with a primary key are expensive because they require disk seeks on large data sets. Towards the end of the post, I claimed that it would be better to use “replace into” or “insert ignore” over normal inserts, because the […]
Jun 22, 2010 |
MySQL
The analysis that shows how to make deletions really fast by using clustering keys and TokuDB’s fractal tree based engine also applies to make updates really fast. (I left it out of the last post to keep the story simple). As a quick example, let’s look at the following statement:
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update foo set price=price+1 where product=toy; |
Executing this statement has […]
Jun 18, 2010 |
MySQL
Continuing in the theme from previous posts, I’d like to examine another case where we can eliminate all disk seeks from a MySQL operation and therefore get two orders-of-magnitude speedup. The general outline of these posts is: B-trees do insertion disk seeks. While they’re at it, they piggyback some other work on the disk seeks. […]
Jun 08, 2010 |
MySQL
In my last post, I discussed how fractal tree data structures can be up to two orders of magnitude faster on deletions over B-trees. I focused on the deletions where the row entry is known (the storage engine API handler::delete_row), but I did not fully analyze how MySQL delete statements can be fast. In this […]
Jun 02, 2010 |
MySQL
As mentioned in parts 1 and 2, having many disk seeks are bad (they slow down performance). Fractal tree data structures minimize disk seeks on ad-hoc insertions, whereas B-trees practically guarantee that disk seeks are performed on ad-hoc insertions. As a result, fractal tree data structures can insert data up to two orders of magnitude […]
May 25, 2010 |
MySQL
In part 1, I discussed why having many disk seeks are bad (they slow down performance), and how fractal tree data structures minimize disk seeks on ad-hoc insertions, whereas B-trees practically guarantee that disk seeks are performed on ad-hoc insertions. As a result, fractal tree data structures can insert data up to two orders of […]
May 20, 2010 |
MySQL
Disk seeks are expensive. Typically, a disk can perform no more than a few hundred seeks per second. So, any database operation that induces a disk seek is going to be slow, perhaps unacceptably slow. Adding disks can sometimes help performance, but that approach is expensive, adds complexity, and anyhow minimizing the disk seeks helps […]
Apr 15, 2010 |
MySQL
Another plug for Bradley’s talk Thursday morning at the MySQL User’s conference. Spending the day talking to DBA’s and other potential users of TokuDB, I (Zardosht) noticed the same question/theme come up numerous times in conversation. “Oh, so your indexes are in memory, that is why iiBench is so much faster for TokuDB than InnoDB”. […]
Nov 17, 2009 |
MySQL
Last spring, we added a feature that allows the user to see the progress of writes in a statement. Vadim liked it. In 2.2.0, in “show processlist”, we add progress information on reads. Here is an example of what “show processlist” displays on an update:
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mysql> show processlist G *************************** 1. row *************************** Id: 1 User: root Host: localhost db: test Command: Query Time: 7 State: Queried about 1576008 rows, Updated about 197000 rows Info: update foo set a=9 where a=8 |
Here is an example of what “show processlist” displays […]
Aug 03, 2009 |
MySQL
In our last post, Bradley described how auto increment works in TokuDB. In this post, I explain one of our implementation’s big benefits, the ability to combine better primary keys with clustered primary keys. In working with customers, the following scenario has come up frequently. The user has data that is streamed into the table, […]