System Troubleshooting

About the Presentation:

This meetup is comprised a couple presentations discussing troubleshooting system performance issues at scale. I was able to get a couple of engineers that work on the EdgeCast Content Delivery Network at our host Verizon Digital Media Services to discuss some interesting issues they encountered and how the problems were resolved.

The first presentation is about troubleshooting the XFS filesystem titled "Trust No 1 (Actually, don’t trust 1’s or 0’s.)" by Will Rosecrans.

Here a description of the presentation...

. "Storage never just works. This talk is a war story that serves as an introduction to hunting down problems related to storage on Linux, based on experiences running the EdgeCast CDN at VDMS. Learn a little bit about how iotop lies to you, and some fun XFS quirks that you never wanted to know about and were afraid to ask."

And here's a little about Will....

Will Rosecrans is a technical lead on the HTTP-Platform team for the Content Delivery Network at VDMS, He has a background in software development and large scale Linux systems administration. Before coming to VDMS he worked on things like render farms for visual effects and academic compute clusters.

There's also a second talk by and engineer to be named later on troubleshooting a performance issue with IPv6 in a vintage linux 3.13 kernel running under the Linux Virtual Server LVS. Systemtap was used to identify and temporarily fix the issue and bug report was submitted to Ubuntu and a the kernel was patched.

There should be ample time for question, and discussion of other troubleshooting experiences.

About the Location:

After turning off of Jefferson on to Alla Road, there is free street parking at the first right Coral Tree Place. From there you can enter the Reserve business park at the Gate 1 main entry which is the gate near the end of the road, or via a pedestrian entrance near gate 2.

Space 900 is the large building that is closest to the Gate 1 main entry.

Special thanks to Verizon Digital Media for hosting this meet up and providing food and beverages.

Unfortunately Verizon Digital Media cannot validate parking in the Reserve so please park on Coral Tree Place and walk in through either gate.

Hangout on Air Info:

This presentation will be live streamed via Google Hangouts On Air with Youtube Live , the link is will be posted here.

https://www.youtube.com/watch?v=gQRl73wsyWs
Note live streaming is somewhat problematic, the stream should come up sometime after 6:30PM on the day of the event. If some cases an new hangout may need to be created so keep an eye on the comments section of this meet up page for any last minute changes.

Also note that video will be edited and posted with a different URL , the URL for the edited version will be posted in the comments section of this meet up page.

About UUASC:

The UUASC (http://uuasc.org (http://uuasc.org/)) is for all persons using UNIX/Linux either personally or professionally, or interested in learning more about UNIX. We recognize all varieties of UNIX, including (without prejudice) BSD, Linux, SVr4, Solaris, AIX, HP/UX, and SCO. This is a good place to meet others with similar interests and broaden your skills and knowledge.

We try to meet on the first Thursday of the month in L.A.

Date and Location Subject to Change:

Note that meet up dates and locations can change on short notice, always check the meetup.com site to see if the information has changed.