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Search Results for: linux raid

MLC SSD card lifetime and write amplification

As MLC-based SSD cards are raising popularity, there is also a raising concern how long it can survive. As we know, a MLC NAND module can handle 5,000-10,000 erasing cycles, after which it gets unusable. …


Review of Virident FlashMAX MLC cards

I have been following Virident for a long time (e.g. https://www.percona.com/blog/2010/06/15/virident-tachion-new-player-on-flash-pci-e-cards-market/). They have great PCIe Flash cards based on SLC NAND. I always thought that Virident needed to come up with an MLC card, and …


Make your file system error resilient

One of the typical problems I see setting up ext2/3/4 file system is sticking to defaults when it comes to behavior on errors. By default these filesystems are configured to Continue when error (such as …


Fast storage: 8 SSD Intel X-25M 80GB benchmarks

I appreciate opportunity Jos van Dongen from Tholis Consulting gave me. He granted me access to servers with 8 attached Intel X-25M 80GB MLC cards. The cards attached to 2 Adaptec 5805 raid controllers, with …


Disaster: LVM Performance in Snapshot Mode

In many cases I speculate how things should work based on what they do and in number of cases this lead me forming too good impression about technology and when running in completely unanticipated bug …


Beware: ext3 and sync-binlog do not play well together

One of our customers reported strange problem with MySQL having extremely poor performance when sync-binlog=1 is enabled, even though the system with RAID and BBU were expected to have much better performance. The problem could …


XtraDB benchmarks – 1.5X gain in IO-bound load

I guess it is first reaction on new storage engine – show me benefits. So there is benchmark I made on one our servers. It is Dell 2950 with 8CPU cores and RAID10 on 6 …


iiBench Contest – Who Can Insert 1B Rows into MYSQL the Fastest?

At the recent OpenSQL Camp in Charlottesville, VA, Tokutek offered a challenge to the MySQL community – who can insert a billion rows into MySQL the fastest?  We will post the results on our website …


How Percona does a MySQL Performance Audit

Our customers or prospective customers often ask us how we do a performance audit (it’s our most popular service). I thought I should write a blog post that will both answer their question, so I …


Living with backups

Everyone does backups. Usually it’s some nightly batch job that just dumps all MySQL tables into a text file or ordinarily copies the binary files from the data directory to a safe location. Obviously both …