… increased usage of CPU time. PZ: We will see how it plays when we can see more benchmarks. The big problems I see…) to swap out MySQL. There are two solutions here. Memlock and O_DIRECT. Memlock is apparently unstable on Linux. O_DIRECT is an… your load is CPU bound and you’re scaling out you can get better performance by using couple of MySQL Servers on…
Post: Effect from innodb log block size 4096 bytes
January 3, 2011 By 19 Comments
… MySQL 5.5.8 and Percona Server: being adaptive I mentioned that I used innodb-log-block-size…average innodb_thread_concurrency=0 innodb_flush_method = O_DIRECT innodb_read_ahead = none innodb_flush_neighbor_…bytes), but I do not know if the effect is the same as on FusionIO. I put CPU usage graph (…
Post: Infinite Replication Loop
October 10, 2011 By 2 Comments
… infinite replication loops. I decided to write a blog post about these infinite loop of binary log statements in MySQL Replication. To… executed. Then that event is replicated to the slaves (the I/O slave thread filters out only the events with a different… monitoring your MySQL server with cacti, you will immediately notice the problem. Look at those graphs: You can see the CPU usage and…
Post: SHOW INNODB STATUS walk through
July 17, 2006 By 40 Comments
…between wasting CPU time running …MySQL thread id 30898, query id 100626 localhost root Updating update iz set pad=’a’ where i…I/O ——– I/O thread 0 state: waiting for i/o request (insert buffer thread) I/O thread 1 state: waiting for i/o request (log thread) I/O…activity and memory usage. You can …
Comment: Linux schedulers in tpcc like benchmark
January 31, 2009 By 19 Comments
…usage among consumers and making decisions about avg vs. worst case latencies vs. throughput, which sometimes does matters. I… (so, latency). I mean workloads including possibles concurrents reads and cpu work, idling … and enforce I/O priorities and arbitration. I‘m not sure whether MySQL do leverage…
Post: Living with backups
November 6, 2008 By 28 Comments
… pattern may be preferred by the I/O scheduler over random I/O coming from MySQL, but also such large I/O requests take significant time to… /root/backup-tools/tar … Please cosult ionice man page for usage details, it’s really very simple to grasp and use… MySQL instance, these are just examples. The cheks can also be more sphisticated or include things like processlist information, CPU load avergages, I/O…
Post: The performance effects of new patches
September 9, 2008 By 14 Comments
…the data bigger than buffer pool (right graph shows CPU usage) The workload emulates TPC-C and has a …time), it uses MySQL C API and the server side prepared statement. The server has 8core CPU and RAID storage… sleep, we assume that there is free disk i/o capacity available, and it makes sense to do …
Comment: Tools
June 1, 2008 By 31 Comments
… this records system informations (interrupts, i/o, load, network traffic, …) at … questions like “why (io, cpu,…) did the system was …usage, this is your tool – strace, ltrace, gdb, tcpdump, … for hard problems Also, I tend to prefer htop over top, and mtr over ping/traceroute. IMHO, MySQL…
Post: Memory allocation in Stored Function
August 26, 2007 By 8 Comments
…I used UPDATE statement, but for avoiding I/O and allocating os cashes let’s check only select: mysql…MySQL allocates memory in each call of Stored Function, but de-allocates it only at the end of statement. This makes usage…
Comment: Is there room for more MySQL IO Optimization?
January 9, 2013 By 11 Comments
…MySQL is not doing that ? Regarding is diagram from Zero values – I have not found how to make Google Charts where I…too. Next time I‘ll probably do everything in Excel instead. Regarding O_DIRECT I do not quite …surely IO bound based on CPU usage stats. I was going to see if I can get the repeatable …
