I am currently working with a large customer and I am involved with servers located in two data centers, one with Solaris servers and the other one with Linux servers. The Solaris side is cleverly setup using zones and ZFS and this provides a very low virtualization overhead. I learned quite a lot about these technologies while looking at this, thanks to Corey Mosher.

On the Linux side, we recently deployed a pair on servers for backup purpose, boxes with 64 300GB SAS drives, 3 raid controllers and 192GB of RAM. These servers will run a few slave instances each of production database servers and will perform the backups.  The write load is not

This is the second part in a two-part series comparing Virident’s vCache to FlashCache. The first part was focused on usability and feature comparison; in this post, we’ll look at some sysbench test results.

Disclosure: The research and testing conducted for this post were sponsored by Virident.

First, some background information. All tests were conducted on Percona’s Cisco UCS C250 test machine, and both the vCache and FlashCache tests used the same 2.2TB Virident FlashMAX II as the cache storage device. EXT4 is the filesystem, and CentOS 6.4 the operating system, although the pre-release modules I received from Virident required the use of the CentOS 6.2 kernel, 2.6.32-220, so that was the kernel in use for all of the benchmarks on

(This is part one of a two part series) Over the past few weeks I have been looking at a preview release of Virident’s vCache software, which is a kernel module and set of utilities designed to provide functionality similar to that of FlashCache. In particular, Virident engaged Percona to do a usability and feature-set comparison between vCache and FlashCache and also to conduct some benchmarks for the use case where the MySQL working set is significantly larger than the InnoDB buffer pool (thus leading to a lot of buffer pool disk reads) but still small enough to fit into the cache device. In this post and the next, I’ll present some of those

Swapping has always been something bad for MySQL performance but it is even more important for HA systems. It is so important to avoid swapping with HA that NDB cluster basically forbids calling malloc after the startup phase and hence its rather complex configuration.

Probably most readers of this blog know (or should know) about Linux swappiness setting, which basically controls how important is the file cache for Linux. Basically, with InnoDB, since the file cache is not important we add “vm.swappiness = 0″ to “/etc/sysctl.conf” and run “sysctl -p” and we are done.

Swappiness solves part of the swapping issue but not all. With Numa systems, the picture is more complex and swapping can occur because of a memory imbalance between the physical cpus, the sockets and not cores. Jeremy Cole explained this

The Micron P320h SSD is an SLC-based PCIe solid-state storage device which claims to provide the highest read throughput of any server-grade SSD, and at Micron’s request, I recently took some time to put the card through its paces, and the numbers are indeed quite impressive.

For reference, the benchmarks for this device were performed primarily on a Dell R720 with 192GB of RAM and two Xeon E5-2660 processors that yield a total of 32 virtual cores. This is the same machine which was used in my previous benchmark run. A small handful of additional tests were also performed using the Cisco UCS C250. The operating system in use was CentOS 6.3, and for the sysbench fileIO tests, the EXT4 filesystem was used. The card itself is the 700GB model.

So let’s take

Facebook is a major user of MySQL and has pushed the performance limits of the technology. Their MySQL experts have deep, hands on knowledge of the technology. I’m pleased to welcome Mark Callaghan, Software Engineer for Database Infrastructure at Facebook, back again this year to the Percona Live MySQL Conference & Expo to share his expertise. Mark was a keynote speaker at last

I’m pleased to announce that Oracle is sending some of their top technical people to speak at the Percona Live MySQL Conference and Expo. The conference takes place April 22-25, 2013 at the Santa Clara Convention Center and Hyatt Santa Clara.

Tomas Ulin, VP, MySQL Engineering for Oracle, will present an invited keynote talk on “Driving MySQL Innovation” during the Tuesday morning opening keynotes. With the recent release of MySQL 5.6, conference attendees will hear about the latest developments of this

There are many reasons for wanting a small MySQL database server:

• You’re a uni student who wants to learn the SQL language better and needs a mini-testbox
• You’re a Windows user who wants to play around with Percona Server on Linux
• You’re a corporate application developer who wants a small SQL development & test box
• You’re a Internet startup that just needs a tiny startup database server without all the added costs

So, how about if you could setup a small Arch Linux ARMv6-based hardware device which runs Percona Server for MySQL, in a space not much bigger than your mouse, with the power consumption of only a smartphone charger, fully networked, all for under $80?

Introducing the Raspberry Pi with Percona Server:

The idea to use SSD/Flash as a cache is not new, and there are different solutions for this, both OpenSource like L2ARC for ZFS and Flashcache from Facebook, and proprietary, like directCache from Fusion-io.
They all however have some limitations, that’s why I am considering to have L2 cache on a database level, as an extension to InnoDB buffer pool.
Fortunately, there is a project in progress Flash_Cache_For_InnoDB by David which implements this.
David helped us to port his work to the latest Percona Server and you can get it from our launchpad Percona Server

Not so far ago Fusion-io announced SDK which provides direct API access to Fusion ioMemory(tm) in addition to providing a native filesystem (directFS) with a goal to avoid overhead from kernel and regular Linux filesystems: ext4 and xfs. Fusion-io will explain these features during our Percona Live New York conference and share performance numbers.

It is not too late to register for conference and talk with Fusion-io engineers directly. “PerconaNY” registration will give you 15% discount.

I have a chance to test Micron RealSSD™ P320h. Initially I was expecting a good performance, but you know, how big could be a difference with other products on market? PCIe SSD market is getting crowded, and every company is trying to show the best performance. And at the end, there is a single PCIe slot, single controller, we are probably about to reach limits of these components.
However I was really surprised to see performance numbers with Micron P320h.
In random reads the throughput is 3200 MiB/sec, while the best results I’ve seen so far was 1450 MiB/sec on single card and 2300 MiB/sec on duo.

And this is 16KiB blocksize, which gives us 200.000 random reads IOP/sec, again in 16K blocks

I continue my benchmarks of Intel SSD 910, previous time I compared it with Fusion-io ioDrive http://www.mysqlperformanceblog.com/2012/09/07/intel-ssd-910-in-tpcc-mysql-benchmark/. Now I want to test this card against RAID over spinning disks.

I continue my benchmarks of Intel SSD 910, the raw IO results are available in my previous experiment. Now I want to test this card under MySQL workload to see if the card is suitable to use with MySQL.

Intel came on PCI-e SSD market with their Intel SSD 910 card. With a slogan “The ultimate data center SSD” I assume Intel targets rather a server grade hardware, not consumer level.
I’ve got one of this card into our lab. I should say it is very price competitive, comparing with other enterprise level PCIe vendors. For a 400GB card I paid $2100, which gives $5.25/GB. Of course I’ve got some performance numbers I’d like to share.

But before that, few words on the card internals. Intel puts separate 200GB modules, so 400GB card is visible as 2 x 200GB devices in operation system, and 800GB card is visible as 4 different devices. After that you can do software raid0, raid1 or raid10, whatever you prefer.

For my tests I used

Every time I have a conversation on SSD, someone mentions btrfs filesystem. And usually it is colored as a solution that will solve all our problems, improve overall performance and SSD in particular, and it is a saviour. Of course it caught my curiosity and I decided to perform a benchmark similar to what I did on ext4 filesystem over Intel 520 SSD.
I was prepared for surprises, as even on formatting stage, mkfs.btrfs says that filesystem is EXPERIMENTAL. In case with filesystems I kind of agree with Stewart, so question #1, what you should ask deciding on what filesystem to use, is “Was this filesystem used in a production more than 5 years?”, so from this point, btrfs has a

I was lucky enough to get my hands on new Fusion-io ioDrive2 Duo card. So I decided to run the same series of tests I did for other Flash devices. This is ioDrive2 Duo 2.4TB card and it is visible to OS as two devices (1.2TB each), which can be connected together via software RAID. So I tested in two modes: single drive, and software RAID-0 over two drives.

I should note that to run this card you need to have an external power, by the same reason I mentioned in the previous post: PCIe slot can provide only 25W power, which is not enough for ioDrive2 Duo to provide full performance. I mention this, as it may be challenge for some servers: some models may not

In my previous post with results for Fusion-io ioDrive we saw some instability in results, I was pointed that it may be fixed in new drivers VSL 3.1.1. I am not sure if this driver is available for everyone – if you are interested, please contact your Fusion-io support representative. I installed new drivers and firmware, and in fact, the result improved.

Information about driver and firmware: Firmware v6.0.0, rev 107006. Fusion-io driver version: 3.1.1 build 172.

Actually an upgrade was not flawless, after a firmware upgrade I had to perform low-level formatting, which erase all data. So if you want to do the same – make sure you copy your data.

So there are results for driver 3.1 (with comparison to previous driver 2.3)

I still continue to run benchmarks of different SSD cards. This time I show numbers for Virident FlashMAX 1400. This is a MLC PCIe SSD device. There are couple notes on these results.
First, this time I use a different server. For this benchmark it is Cisco UCS C250, while for previous results I used HP ProLiant DL380 G6.

Second note is, that I use a mode “turbo=1″ for Virident card. What does that mean? Apparently PCIe specification has a limitation on available power. If I am not mistaken it is 25W, however Virident to provide full write performance requires 28W. And while many servers can handle 28W on PCIe, this is a non-standard mode, and Virident by default uses 25W (turbo=0). To force full power, I load a driver with

Following my series of posts on testing different SSD, in my last post I mentioned that SATA SSD performance is getting closer to PCIe cards. It really makes sense to test it under MySQL workload, but before getting to that, let me review the same workload on Fusion-io ioDrive PCIe card. This is yet previous generation of Fusion-io cards, but this is the one that has biggest installation base.

Driver information: Fusion-io driver version: 2.3.10 build 110; Firmware v5.0.7, rev 107053

Following the format of previous benchmarks, first is random write async 16KB case.

We can see

Following my previous benchmarks of SATA SSD cards I got Intel SSD 520 240GB into my hands. In this post I show the results of raw IO performance of this card.

The benchmark methodology I described in previous posts, so let me jump directly to results.

First case is random write asynchronous 8 threads IO, the test is done just after a secure erase operation on the card.

Following my previous benchmark of Samsung 830, today I want to show results for STEC MACH16 SATA card, 200GB size, this card is based on SLC, and regarding STEC website, it is an enterprise grade storage.

For tests I use sysbench fileio, 16KiB block size (to match workload from InnoDB, as this is primary usage for me), and recently I switched to use async IO mode. There are two reasons for that. First, MySQL/InnoDB uses async writes, so this will emulate database load, and second, async mode allows to see maximal possible throughput, it does not show reliable latency though, as it appears there is no a reliable way in the Linux asynchronous IO

I personally like PCIe based Flash, but from a pricing point our customers are looking for cheaper alternatives. SATA SSD is an options. There is many products based on MLC technology, and Intel 320 I would say is the most popular. I do not particularly like its write performance – I wrote about it before, that’s why I am looking for comparable alternatives. Samsung 830 256GB looked like a good product, that’s why I decided to test it.

For tests I use sysbench fileio, 16KiB block size (to match workload from InnoDB, as this is primary usage for me), and recently I switched to use async IO mode. There are two reasons for that. First, MySQL/InnoDB uses async writes, so this will emulate database load,

I’m excited by all of the recent developments surrounding the Percona Live MySQL Conference and Expo! Our own Baron Schwartz will moderate the Diamond Keynote Panel entitled “Future Perfect: The Road Ahead for MySQL” which will feature a panel of MySQL industry leaders, including: Sundar Raghavan, director product management at Amazon; Paul Mikesell, CEO of Clustrix; a representative from HP; and, a representative from McAfee. The Diamond Sponsor Keynote Panel will take place at 9:30 a.m. on Thursday, April 12th and provide insight into the future of MySQL technology, adoption, and the ecosystem landscape. I am also very pleased to

The Percona Live MySQL Conference & Expo is going to be awesome! Great speakers, an A-list of sponsors, countless opportunities to engage with the community, and an enthusiastic crowd of MySQL users ensure this is going to be a great event. The conference features 72 breakout sessions, keynotes by leading industry luminaries, an optional day of 16 tutorial sessions, a bustling exhibit hall, and numerous opportunities to connect with other community members.

I am pleased to announce the conference Birds of a Feather sessions and Lightning Talks.

If you are terrified by the stability of the results in MySQL in my previous post, I am going to show what we can get with Percona Server. This is also to address the results presented there Benchmarking MariaDB-5.3.4

The initial benchmark is described in Benchmarks of Intel 320 SSD 600GB, and the result for MySQL 5.5.20 in case with 4 (46GB of data) and 16 tables (184GB of data) you can see in my experiments with R graphics.

How do we solve it in Percona Server ? There is whole set of improvement

I have a chance to test a system with Intel 320 SSD drives (NewRelic provided me with an access to the server), and compare performance with SAS hard drives.

System specification

• Dell PowerEdge R610
• Memory: 48GB
• CPU: Intel(R) Xeon(R) CPU X5650
• RAID controller: Perc H800
• RAID configuration: RAID 5 over 11 disks + 1 hot spare. RAID 5 is chosen for space purposes. In this configuration using 600GB disk, we can get 5.5T of useful space
• Intel drives: Intel 320 SSD 600GB
• HDD drives: Seagate Cheetah 15K 600GB 16MB Cache SAS
• Filesystem: XFS, mkfs.xfs -s size=4096, mount -o nobarrier

Benchmark:
For the benchmark I took a sysbench uniform oltp rw workload. 256 tables, 50mil rows each, which gives in total 3T of data.
To vary a

Preparing Choosing Storage Systems for MySQL talk for Percona Live in Washington,DC I ran into great paper called Sane SAN 2010 by James Morle from Scale Abilities – and Oracle consulting company. It is worth to read for variety of reason yet for this post I wanted to mention what James calls “Busy” Oracle database application when it comes to IO consumption:

It is applications either using Over 10.000 IOs Per second (latency sensitive) or using Over 500MB/s bandwidth (bandwidth sensitive). I wonder how many of MySQL Users

As I mentioned in previous post on Virident FlashMAX MLC, beside sysbench benchmark, I also run tpcc-mysql (to compare performance Virident FlashMAX vs Fusion-io ioDrive Duo)

The report with results is there: http://www.percona.com/files/white-papers/virident-mlc-tpcc.pdf

The graphical result for tpcc-mysql 5000W:

My conclusions from this benchmark:

• Virident FlashMAX provides stability of performance and reveals a denser

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. And obviously the SSD card based on MLC NAND has a limited lifetime. There is a lot of misconceptions and misunderstanding on how long such card can last, so I want to show some calculation to shed a light on this question.

For base I will take Virident FlashMAX M1400 (1.4TB) card. Virident guarantees 15PB (PB as in petabytes) of writes on this card.
15PB sounds impressive, but how many years it corresponds to ? Of course it depends on your workload, and mainly how write intensive it is. But there are some facts that can help you to estimate.

On Linux you can look into the

I have been following Virident for a long time (e.g. http://www.mysqlperformanceblog.com/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 I am happy to see they have finally done so.

At Virident’s request, I performed an evaluation of their MLC card to assess how it handles MySQL workload. As I am very satisfied with the results, I wish to share my findings in this post.

But first, I wish to offer an overview of the card.