Archive for the ‘filesystem’ Category

Manta: Unix Meets Map Reduce

Today Joyent launched Manta: an object store built upon ZFS and Zones, the SmartOS platform, and with a familiar Unix interface as the API. This supports compute jobs such as map reduce, and provides high performance by co-locating zones with the object storage. We also have extensive DTrace instrumentation throughout the product, which we’ve been [...]

Posted on June 25, 2013 at 6:32 am by Brendan Gregg · Permalink · Comments Closed
In: filesystem, joyent, manta

File System Latency: part 5

This is part 5 of File System Latency, a series on storage I/O performance from the application perspective (see parts 1, 2, 3 and 4). Previously I explained why disk I/O metrics may not reflect application performance, and how some file system issues may be invisible at the disk I/O level. I then showed how [...]

Posted on June 3, 2011 at 12:02 pm by Brendan Gregg · Permalink · Comments Closed
In: cloud analytics, DTrace, filesystem, latency, mysql, performance, vfsstat

File System Latency: part 4

This is part 4 on file system latency, a series on storage I/O performance from the application perspective (see part 1, part 2 and part 3). In the previous post I showed how to trace file system latency from within MySQL using the pid provider. In this post I’ll show how similar data can be [...]

Posted on May 24, 2011 at 5:57 pm by Brendan Gregg · Permalink · Comments Closed
In: DTrace, filesystem, latency, mysql, performance

File System Latency: part 3

This is part 3 on file system latency, a series on storage I/O performance from the application perspective (see part 1 and part 2). Here I’ll show how to actually measure file system I/O latency – the time spent waiting on the file system to complete I/O. Examining this can save a lot of time [...]

Posted on May 18, 2011 at 9:28 am by Brendan Gregg · Permalink · Comments Closed
In: DTrace, filesystem, latency, mysql, performance

File System Latency: part 2

This is part 2 of File System Latency, a series on storage I/O performance from the application perspective. In the first part I explained why disk I/O is difficult to associate with an application, and why it can be altered from what the application requested. In this part I’ll focus more on the file system, [...]

Posted on May 13, 2011 at 12:26 pm by Brendan Gregg · Permalink · Comments Closed
In: DTrace, filesystem, latency, mysql, performance

File System Latency: part 1

When considering I/O performance from the perspective of applications, file systems can prove to be a better target for analysis than disks. With modern file systems using more DRAM-based cache and performing more asynchronous disk I/O, what the application experiences can vastly differ to what the disks are doing. I’ll demonstrate this by examining I/O [...]

Posted on May 11, 2011 at 6:47 pm by Brendan Gregg · Permalink · Comments Closed
In: DTrace, filesystem, latency, mysql, performance