v1.1.7 performance decrease after 2 hour 1080p playback

[hermo_menee]

Hi,

I've been experienceing serious performance problems in VLC 1.1.7 with 1080p mkv files. After approximately 2 hours of continuous viewing video starts to twitch and jerk, especially in fast moving scenes. Things get worse and worse the longer you watch the movie. I just finished Schindler's List which is about 3 hour movie. At the end the movie was almost unwatchable. When I tried to quit VLC the whole computer was jammed and I had to force quit VLC. This happens with every long movie after approx. 2 hours (1080p mkv files). Any solution to this? My computer indeed has enough power to playback a 1080p movie smoothly (27" iMac with Intel i5 + 8GB RAM).

[roger jonsson]

This problems comes up and is answered about each and every week...

Go to Preferences-->All-->Input / Codecs-->Access modules-->MMap
Deselect "Use file memory mapping".
Save.
Restart VLC.

At some time ago MMap was enabled by default. It is now disabled (I think), but if you have had an earlier version before, the old MMap setting is stored. MMap uses ram to cache the movie and improves performance. -As long as there is memory left. When all ram has been chewed up the computer gets severely crippled...

[hermo_menee]

I saw the sticky post but I didn't realize it was about this same problem, sorry for that . I have the latest version and I thought the setting was correct there... but it wasn't. VLC installer should reset the settings or something to avoid stupid problems like these .

Btw, how does the memory mapping actually work. If I have, let's say, 6GB free RAM and I'm watching a 4,5GB mkv file does VLC use at maximum 4,5GB RAM > no performance issues?

[roger jonsson]

Yes I think so. It is OS X that by default caches the file, so the free memory lost will be the same as the file size read. When it comes to watching movies caching is not much use, since you normally only ready the file once. It is a different story about other stuff that is being read over and over again (editing, libraries, routines etc).

Generally I don't think that a new version should reset user settings, but something should be done with this particular setting since it has obviously caused problems for so many.