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Datacenter

2.6.34 is Out; Let’s Review
If you blinked you might have missed the announcement of the new 2.6.34 kernel. Things have been happening very quickly around file systems and storage in the recent kernels so it's probably a good idea to review the kernels from 2.6.30 to 2.6.34 and see what developments have transpired.
Creating a NAS Box with an Existing System
Standalone Network Attached Storage (NAS) servers provide file level storage to heterogeneous clients, enabling shared storage. This article presents the basics of NAS units (NFS servers) and how you can create one from an existing system.
Saving Your Data Bacon with Write Barriers and Journal Check Summing
Mmmm.... bacon. This article examines two mechanisms to prevent data loss -- write barriers and check summing. Both can be particularly important for drives with larger and larger caches. Pay attention: This can save your data bacon.
Smartmontools: Ya Mon!
Last article we introduced the SMART capabilities of hard drives (who knew your drives were SMART?). In this article smartmontools, an application for examining the SMART attributes and trigger self tests, is examined.
Introduction to SMART
Did you know your drive was SMART? Actually: Self-Monitoring, Analysis, and Reporting Technology. It can be used to gather information about your hard drives and offers some additional information about the status of your storage devices. It can also be used with other tools to help predict drive failure.
Storage Technology for the Home User
Sometimes you just have to get excited about what you can buy, hold in your hand, and use in your home machines. Let's look at some cool storage technology that the average desktop user can tackle.
Ceph: The Distributed File System Creature from the Object Lagoon
Did you ever see one of those terrible Sci-Fi movies involving a killer Octopus? Ceph, while named after just such an animal, is not a creature about to eat an unlucky Spring Breaker, but a new parallel distributed file system. The client portion of Ceph just went into the 2.6.34 kernel so let's learn a bit more about it.
Harping on Metadata Performance: New Benchmarks
Metadata performance is perhaps the most neglected facet of storage performance. In previous articles we've looked into how best to improve metadata performance without too much luck. Could that be a function of the benchmark? Hmmm...
IO Profiling of Applications: strace_analyzer
In the last couple of articles we have talked about using strace to help examine the IO profile of applications (including MPI applications; think HPC). But strace output can contain hundreds of thousands of lines. In this article we talk about the using a tool called strace_analyzer to help sift through the strace output.
IO Profiling of Applications: MPI Apps
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In the last article we looked at using strace to examine the IO patterns of simple serial applications. In the High Performance Computing (HPC) world, applications use MPI (Message Passing Interface) to create parallel applications. This time around we discuss how to attack parallel applications using strace.
Intro to IO Profiling of Applications
One of the sorely missing aspects of storage is analyzing and understanding the IO patterns of applications. This article will examine some techniques for performing IO profiling of an application to illustrate what information you can gain.
POSIX IO Must Die!
POSIX IO is becoming a serious impediment to IO performance and scaling. POSIX is one of the standards that enabled portable programs and POSIX IO is the portion of the standard surrounding IO. But as the world of storage evolves with greatly increasing capacities and greatly increasing performance, it is time for POSIX IO to evolve or die.
Geeking Out on SSD Hardware Developments
When you're hot, you're hot. And SSD's are hot right now. Let's review recent developments in SSD hardware and to see where the technology is headed. Prepare to drool over new hardware!
Size Can Matter: Throughput Performance with a Disk-Based Journal – Part 4
Turning from Metadata performance to throughput performance, we examines the impact of journal size on ext4 when the journal is disk-based. Dig into the numbers and see what you can do to improve throughput performance.
Size Can Matter: Would You Prefer the Hard Drive or the Ramdisk this Evening? Part 3
The past couple of weeks we ran the numbers on metadata performance for ramdisks and hard drive-based journals for ext4. Now let's compare/contrast the two journal devices and see what trends emerge.
Size Can Matter: Ramdisk Journal Metadata Performance – Part 2
Previously, we examined the impact of journal size using a separate disk on metadata performance as measured by fdtree. In this follow-up we repeat the same test but use a ramdisk for the journal, thereby boosting the best performance. Or does it?
Size Can Matter: Improving Metadata Performance with Ext4 Journal Sizing – Part I
Recently we saw that the journal device location, unfortunately, didn't make much of a difference on ext4 metadata performance. But can the size of the journal will have an impact on metadata performance? The first in a series of articles examining the journal size and performance.
And the Sign of the Beast is 6 (Gbps that is)
In the quest for more performance there are two new standards for SATA and SAS focused on doubling current throughput to 6 Gbps. While the standards may sound like a nice potential boost don't expect individual hard drives to increase in performance.
Improving MetaData Performance of the Ext4 Journaling Device
In the never-ending quest for more performance, we examine three different journaling device options for ext4 with an eye toward improving metadata performance. Who doesn't like speed?
Storage Highlights of 2009
It's the end of the year and that means it's time to either make predictions for the coming year or review the highlights from the past year. This article takes a look at the cool things that happened around storage in the past year and perhaps hints at some things in the coming year.