Why does pausing stop flashvideos from lagging?

Question

This is a more theoretical question:

When I'm watching larger videos (> 15 min) on the internet via flashplayer or divx, after some minutes, the video quality begins to decrease (like the video starts lagging). When I now press the pause button and resume the playing after a short period of time, like 10 seconds, the video quality is again like normal for another couple of minutes, but then the video quality again decreases, so I have to pause again for some seconds.

My question is, from a software design point-of-view, why does the pausing stop the video from lagging? I thought it could be because the software gets time to refresh its caches, but I would be really interested in the correct answer.

score 1 · Accepted Answer · answered Mar 10 '11 at 22:55

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Try youtube. It shows how is the buffer that serves as the read-ahead buffer is full. When it is exhausted (due to slower connection) the video will start to degrade and slow down. Pausing causes read-ahead buffer to fill again.

answered Mar 10 '11 at 22:55

Daniel Mošmondor

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Yes, this obviously a reason, but I'm talking about the lagging that occurs even if the read-ahead-buffer is fully loaded. – kohlehydrat Mar 11 '11 at 13:44
Slow CPU? did you try to take a look at the CPU usage? – Daniel Mošmondor Mar 11 '11 at 14:06
yes, my cpu is not very fast, but it doesn't explain why it becomes better after pausing the video. – kohlehydrat Mar 11 '11 at 14:09
Hm - maybe it is the buffering, and the buffering indicator is showing incorrect data. – Daniel Mošmondor Mar 11 '11 at 14:45

score 1 · Answer 2 · answered Mar 11 '11 at 09:37

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Sounds more like a memory problem. When you're thrashing memory - grabbing it, then having to delete more before you can grab again - it affects performance, which in this case looks like the video is lagging

answered Mar 11 '11 at 09:37

divillysausages

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Why does pausing stop flashvideos from lagging?

2 Answers2