How to test performance


bah1976

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I remember in 4.7 there used to be something about a bandwidth monitor and disk performance monitor, but I can't seem to find those in 6B9. (or any of the v6's I've had over the past while)  Is there a plugin or something I can add in to see that? 

 

My config is this:  In addition to the typical unraid stuff, I've got a xen VM running ubuntu and mythtv running as a primary backend.  It records from a hdhomerun tuner and writes to a nfs mounted file system on unraid.  I then have a second HTPC type machine running mythtv frontend for video output.  The NFS share I use is configured to use my cache drive - currently a Seagate ST1000DM003.  When I am recording a show and trying to view it at the same time, it stutters - and this is the problem I'm trying to track down.  top shows no CPU or memory bound processes, so it must either be my 1G network connectivity or cache disk performance, but I don't know how to figure out which.  I also have some docker containers running but those aren't related to this issue.

 

I'm leaning toward the disk, and therefore considering a SSD for cache, but I want to be sure before I spend the $$. 

 

Any thoughts? 

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I remember in 4.7 there used to be something about a bandwidth monitor and disk performance monitor, but I can't seem to find those in 6B9. (or any of the v6's I've had over the past while)  Is there a plugin or something I can add in to see that? 

I believe that was unmenu.  Dynamix might be another possibility, not sure.
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So - in case anybody is curious -

I found unmenu and got the performance, I/O did not look overly taxed.  I then found this link:

 

https://forums.freenas.org/index.php?threads/help-me-optimize-for-mythtv-simultaneously-reading-and-writing-2-gb-mpeg2-files.22058/#post-131032

 

There is some indication that there are some bugs in the mythtv side of reading from an actively recording file over NFS.  I followed that suggestion and now have all recordings going to the local HTPC disk, and every night at 1am it copies them over to unraid where they're placed onto the cache drive, and then the mover script moves them the rest of the way to protected disks.  It is quite a process, but it keeps the family happy when they start watching survivor 20 minutes late.

 

Thanks for the input.

 

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