Category: Performance
Hits: 2034

Performance collection files like *.etl and *.blg files I work with on a daily basis as a performance consultant. Collecting the files is quite easy, working with them can be teadious. Especially when the log files are seperated (because you don't want logging to be the bottleneck in the performance and you schedule log creation for once in the x minutes).

working with performance collection filesXperf

Because opening the different log files can be very time constraining and not give the entire view of the timeline, I like to merge files. The two different log file types need to be merged on a different way. The ways are by Xperf (Explanation here) and by relog (Explanation here).

Merging the performance collection files

To do a merge of *.etl files do the following:

  1. Open powershell
  2. Browse to the location of the Logfiles
  3. enter: $Test=get-childitem -recurse -include *.etl
  4. after that enter: xperf -merge $test MergedETL.etl

When merging *.blg files use the following procedure:

  1. Open powershell
  2. Browse to the location of the Logfiles
  3. enter: $test=get-childitem -recurse -include *.blg
  4. After that enter: relog $test -f BIN -o mergedlogs.blg

Make sure that when merging *.blg files you do not have more then 32 files and that there are no empty (400 kb) files.

After merging the files you can go on analysing the performance collection files. You can use your own favorite tooling to do the analysis. I will spend a following blog about which tooling I use and for what cause.

If you have any questions or remarks after reading this article feel free to hit me up with your questions or remarks, I will try to get back at you as soon as possible and where possible update this blog post to corresponded with your question or remark.