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http://avisynth.nl/index.php/Internal_f ... _functions
PS 都开始认亲了(扶额…Sets the maximum memory that AviSynth uses (in MB) to the value of amount. Setting to zero just returns the current Memory Max value. v2, (=0) v2.58. In the 2.5 series the default Memory Max value is 25% of the free physical memory, with a minimum of 16MB.
From v2.58, the default Memory Max is also limited to 512MB.
Free memory <64 128 256 512 1024 2048 3072
Max v2.57 and older 16 32 64 128 256 512 768
Default Max since v2.58 16 32 64 192 448 512 512
In some versions there is a default setting of 5MB, which is quite low. If you encounter problems (e.g. low speed) try to set this values to at least 32MB. Too high values can result in crashes because of 2GB address space limit.
Return value: Actual MemoryMax value set.