…connect_errors was raised from 10 to 100 which is good change to reduce the potential of blocked host errors…larger by default as value of 1M is too small to be practical if someone tries to… case very welcome change to help workloads with many connects/disconnects sync_relay_log_info and sync_master…
Post: Review of MySQL 5.6 Defaults Changes
October 8, 2012 By 10 Comments
… there are a lot of good changes and many defaults are now computed instead of hardcoded. Though …installations innodb_log_file_size = 48M This is still too small for any real load but a lot … max_connect_errors = 100 10 or 100 does not make much difference if you get some sporadic network errors …
Comment: table_cache negative scalability
April 14, 2010 By 23 Comments
… I start getting errors such as: 100414 0:21:52 [ERROR] Error in accept: Too many open files 100414 0:21:52 [ERROR] /usr/local/mysql…) [root@wcdb /db]# perror 24 OS error code 24: Too many open files I have this many MyISAM tables: [root@xxx /db/mydata]# find… days. long_query_time = 2 thread_cache_size = 100 max_connections = 400 table_cache = 20000 open_files_limit = 40000 max_binlog…
Post: 10+ Ways to Crash or Overload MySQL
November 13, 2007 By 20 Comments
… this issue by killing transactions which are too old though proper solution would be implementing … number of failed connections. This can be avoided by having high max_connect_errors variables but this … restrict abusers. This is not to mention many Virtual Hosting companies use old MySQL versions …
Post: Aligning IO on a hard disk RAID – the Benchmarks
June 9, 2011 By 13 Comments
…200 port = 3306 back_log = 50 max_connections = 2500 max_connect_errors = 10 table_cache = 2048 max_allowed_packet… threads. Different file sizes made no difference too. Write-back cache gave an incredible performance … setting might be a [mirrored] RAID0 with many more stripes as not having proper …
Comment: table_cache negative scalability
April 14, 2010 By 23 Comments
… I start getting errors such as: 100414 0:21:52 [ERROR] Error in accept: Too many open files 100414 0:21:52 [ERROR] /usr/local/mysql… [ERROR] /usr/local/mysql/bin/mysqld: Can’t open file: ‘./wc_miehr_posasmp/panel_decert.frm’ (errno: 24) I have this many… days. long_query_time = 2 thread_cache_size = 100 max_connections = 400 table_cache = 20000 open_files_limit = 40000 max_binlog…
Post: Replaying database load with Percona Playback
October 25, 2012 By 9 Comments
… 330501 slower. We also see that some queries had errors. Those error are shown on the stderr so you can redirect them… typical reason for an error is that a particular query returns different number or rows. For example: Connection 43 Rows Sent: 210… had errors. Expected 372462 rows, got 371851 (a difference of 611) Number of queries where number of rows differed: 324. Not too many…
Post: New SpecJAppServer results at MySQL and Sun.
November 12, 2008 By Leave a Comment
…READ-COMMITTED max_allowed_packet = 1M max_connections=300 max_connect_errors=100 table_cache = 6000 read_rnd_…READ-COMMITTED – this is indeed good setting for many workloads so unless you have repeatable … Benchmark optimization. Such large logs typically will cause too long recovery time in case of …
Post: How Percona does a MySQL Performance Audit
November 24, 2008 By 17 Comments
… throw at databases Many people assume their … get this information, too. The last three…Variable_name | Value | +———————————–+———————-+ | Aborted_clients | 205174 | | Aborted_connects | 29 | | Binlog_cache_disk_use | 0…look at the error log. The error log shows all…
Post: How Percona diagnoses MySQL server stalls
March 3, 2011 By 6 Comments
…error” part of “trial-and-error.” At Percona we have become skilled at diagnosing these types of problems, and we can solve many… thing to check for. VARIABLE=${VARIABLE:-Threads_connected} You need to change the threshold … and sometimes the problem is doing too much work without blocking. Likewise, …
