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.
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 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.
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!
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.
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.
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?
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.
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.
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?
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.
Everyone loves a shiny new kernel. The latest one, 2.6.32, was released on Dec. 3 and there are some nice updates/fixes for file systems and IO in general. But there is a very important change for the CFQ IO scheduler that you need to understand.
The SuperComputing Conference/Exhibition is always a great conference for learning about storage trends in the HPC world. This year the alert attendee could spot two emerging trends: smaller companies developing innovative storage solutions and the rise of flash storage units.
Cloud Storage -- while perhaps not the best label ever invented -- holds promise for the massive future storage requirements looming on the horizon. And does it at a very good price/performance ratio. This article takes a quick look at the concepts and the challenges of Cloud Storage.
iSCSI is one of the hottest topics in Storage because it allows you to create centralized SANs using TCP networks rather than Fibre Channel (FC) networks. Get a handle on the main iSCSI concepts and terminology.
The last article talked about the anatomy of SSDs and the origins of some of the their characteristics. In this article, we break down tuning storage and file systems for SSDs with an eye toward improving performance and helping overcome some of the platform's limitations.
SSDs (Solid-State Drives) are a hot topic right now for a number of reasons; not the least of which being their power to performance ratio. But to better understand SSDs you should first get a grip on how they are constructed and the features/limitations of these drives.
A fairly common Linux storage question: Which is better for data striping, RAID-0 or LVM? Let's take a look at these two tools and see how they perform data striping tasks.
The last article was a quick overview of the 4 schedulers in the Linux kernel. This article takes a closer look at the Completely Fair Queuing (CFQ) scheduler and how you can tune it.
The Linux kernel has several different IO schedulers. This article provides an introduction to the concept of schedulers and what options exist for Linux.
We finish off our IOzone performance exploration of the major Linux file systems. This time adding ext2, jfs, xfs, btrfs, and reiserfs. Let's take a look at the numbers.
One of the hottest topics in the enterprise storage world is deduplication. We take a look at the technology behind the concept and discuss where it is best applicable in your storage strategy.
While metadata performance is important, another critical metric for measuring file systems is throughput. We put three Linux file systems their paces with IOzone.
More performance: We add five file systems to our previous benchmark results to creating a "uber" article on metadata file system performance. We follow the "good" benchmarking guidelines presented in a previous article and examine the good, the bad and the interesting.
Backups are a technology or process that everyone -- everyone! -- needs to consider. This article looks at some on-line backup options for Linux that can apply to the spectrum of home to enterprise-class users.
Linux comes with software-based RAID that can be used to provide either a performance boost or add a degree of data protection. This article gives a quick introduction to Linux software RAID and walks through how to create a simple RAID-1 array.
Benchmarking has become synonymous with marketeering to the point it is almost useless. This article takes a look at a very important paper that can demonstrate how bad it has become and makes recommendations on how to improve the situation.
Jeff Layton talks to Valerie Aurora, file system developer and open source evangelist, about a wide range of subjects including her background in file systems, ChunkFS, the Union file system and how the developer ecosystem can chip in.
There is a new file distributed file system in the staging area of the 2.6.30 kernel called POHMELFS. Sporting better performance than classic NFS, it's definitely worth a look.
Ramdisks can offer a level of performance that is simply amazing. More than just a tool for benchmarking, there are new devices that utilize ramdisks for a bit of the ultra-performance.
Who knew that compression could be so useful in file systems? SquashFS, typically used for embedded systems, can be a great fit for laptops, desktops and, yes, even servers.
The 2.6.30 kernel is chock full of next-gen file systems. One such example is NILFS, a new log-structured file system that dramatically improves write performance.
Need details on your file system's data? FS_scan allows you dig deep into your storage, giving you the ability to perform trend analysis on the results.