Freezing every few minutes with 3.5.3.0-18

[diegov 21]

Hi there,

 

I've just upgraded to a Synology DS918+ and installed 3.5.3.0-18. No issues with the installation.

 

What I have noticed is the Emby Interface and Live TV in particular freezes every few minutes. Movies and TV shows are less affected due to the way they buffer.

 

I believe the freezing is due to the mono process going to sleep. When i look at processes during a freeze mono is sleeping, when emby unfreezes mono moves back to running status.

 

This issue makes Live TV unwatchable.

 

Any way to keep the mono process alive or other suggestions?

 

Pictures of Synology task manager attached

 

Thank you

Diego

Edited November 23, 2018 by diegov

[solabc16 379]

Hello @@diegov

 

If possible, can you run the send logs utility : https://github.com/MediaBrowser/Wiki/wiki/Synology-:-How-to-Send-us-Support-Logs

 

When it completes you'll get a reference, post that here.

 

There will typically be more than one Mono process running, you can sort by that column to make it easier to see them all; I suspect this is a red herring though.

 

Best

- James

Edited November 23, 2018 by solabc16

[diegov 21]

Hi James,

 

Thanks for your reply. I was doing some investigation and it may be the disc scrubbing process causing the issues. With disc scrubbing on, Live TV and the Emby interface will freeze every few minutes, when scrubbing is complete things appear to be ok again.

 

I've sent you the logs which have been captured post a freeze event for you to analyze:

 

sendlogs_diskstation_synology_apollolake_918+_20181123T190847UTC.tgz

 

If this is indeed cause by a disc scrub, is there any workaround? I only ask as disc scrub is a maintenance process which is regularly scheduled.

 

Thanks in advance.

Diego

[Luke 37010]

What do you mean by disc scrubbing? What is that?

[diegov 21]

What do you mean by disc scrubbing? What is that?

It is a function / process on the Synology that verifies the file system and raid groups for errors. Its run in the background on a schedule to proactively protect against data corruption.

Edited November 23, 2018 by diegov

[solabc16 379]

Hello

 

Here's a paragraph from the IBM systems we work on... "Media scan is a background process enabled by default that checks logical drives over hard disk drives for defects by reading the raw data from the disk and writing it back. This detects possible problems caused by bad sectors of the physical disks before they could eventually disrupt normal data reads or writes. This process is sometimes known as data scrubbing."

 

@@diegov, how this impacts your system will depend on a few factors, but you are going to experience a drop in performance which may be significant enough to have a noticeable impact.

 

How often to do you have it scheduled to run?

 

Best

- James

Edited November 23, 2018 by solabc16

[diegov 21]

Hi James,

 

I have it set to run once a week and can schedule it at night, so no drama there.

 

It's curious as my CPU and RAM usage are very low during a disc scrub, everything else works smoothly eg, DSM, file shares, opening a movie direct from from CIFS. The intermitent freezing from Emby is a little odd as I would imagine serving up the Interface would be very light on resources and Live TV, apart from the ffmpeg cache for direct streaming, would not demand much resources. Maybe the system down prioritizes third party processes during a disc scrub?

 

1 hour on, and things look ok, so it does appear that disc scrubbing is the culprit.

 

Thanks again for your help! Hopefully this post may help another user with a new Synology, as disc scrub is automatically kicked on when you initialize your drives or expand.

 

Thanks!

Diego

Edited November 23, 2018 by diegov