…10% or 80% and you really need to understand how DRBD works as well as how IO system is utilized to understand how much overhead…backed up unit) on your hardware RAID card or something which has same…overhead as a number but learn where this overhead comes from so you can find how much would it be for…
Post: Innodb Double Write
August 4, 2006 By 24 Comments
…between their execution. Reasons for splitting could be file fragmentation… Same happens with Hardware RAID on power failure if…How much does double write buffer affect MySQL Performance ? Even though double write requires each page written twice its overhead… no more than 5-10% performance loss due to…
Post: MLC SSD card lifetime and write amplification
November 15, 2011 By 8 Comments
…raising concern how long it can survive. As we know, a MLC NAND module can handle 5,000-10,…1 (meaning there is no overhead) for sequential writes and it gets a maximum value for fully random writes. This value…not know and 2. A throughput on regular RAID is much less than on SSD and you do not know…
Post: MySQL 4 to MySQL 5 Upgrade performance regressions
June 6, 2007 By 8 Comments
… just 5-10% you often see for simple … how MySQL handled this problem. While working for …should not have hardware RAID or have one without…much traction inside MySQL – because paying customers would normally have enough money to get BBU unit which is great for…XA support has its overhead anyway so you …
Post: Group commit and real fsync
May 3, 2006 By 9 Comments
…10 times in certain cases. What was the most surprising for… just couple of percent overhead. So what is …much smaller, especially with large transactions. So how you can solve the problem ? Disable binary log. This could be option for slaves for… extra tests for fsync() correctness. Install RAID with …
Post: Beware: ext3 and sync-binlog do not play well together
January 21, 2009 By 19 Comments
… even though the system with RAID and BBU were expected to have much better performance. The problem could…sec with sync-binlog=0 which is about 10% overhead. EXT2 filesystem also behaves similar to XFS so…know results. You also may wonder how could this problem be unnoticed for a while ? First it …
