2022-04-25, 21:49
Hi there, I have identified that the behaviour documented on the "Modify the video cache" wiki page is totally wrong.
The wiki article says that the value specified in <memorysize> dictates the actual size of the buffer and that 3x this amount needs to be available in system RAM.
However, what actually happens is that <memorysize> represents a total that is 2x the buffer amount. It looks like it dictates a total of which 50% is used for a rolling cache. 1GB set results in a 500MB buffer, 2GB set results in a 1GB buffer.
Further to this, the cache wiki says there must be 3x the memorysize value available in RAM for this to work without issue. This also appears to be incorrect. System memory on my Pi4 is only showing as the usual 3-400MB + the actual size of the rolling cache. So with 2GB set, this appears to result in 1GB extra utilisation.
Just wanted to highlight this so someone can confirm my findings and update the wiki.
The wiki article says that the value specified in <memorysize> dictates the actual size of the buffer and that 3x this amount needs to be available in system RAM.
However, what actually happens is that <memorysize> represents a total that is 2x the buffer amount. It looks like it dictates a total of which 50% is used for a rolling cache. 1GB set results in a 500MB buffer, 2GB set results in a 1GB buffer.
Further to this, the cache wiki says there must be 3x the memorysize value available in RAM for this to work without issue. This also appears to be incorrect. System memory on my Pi4 is only showing as the usual 3-400MB + the actual size of the rolling cache. So with 2GB set, this appears to result in 1GB extra utilisation.
Code:
LibreELEC (official): 10.0.2 (RPi4.arm)
LibreELEC:~ # free -m
total used free shared buff/cache available
Mem: 7759 1365 6087 36 306 6250
Swap: 0 0 0Just wanted to highlight this so someone can confirm my findings and update the wiki.
