tmpfs doesn't update free memory stats?

Jacek Kopecky
2001-05-04T10:10:15Z

Hello. 8-)
I'm not in the list, please cc your replies to me.
After upgrading to 2.4.4 I started using tmpfs for /tmp and I
noticed a strange behavior:

dd if=/dev/zero of=blah bs=1024 count=102400
# increased my used swap space by approx. 100MiB (correct)
rm blah
# did not decrease it back

Multiple retries showed what looked like a random behavior of
the used swap stats. Is this a correct behavior? Should the swap
stats be dismissed as 'unreliable'? I expected that when creating
a 100MiB file in memory it should increase the swap (or memory)
usage by cca 100MiB and that removing a file from tmpfs means
freeing the memory.
Best regards

Jacek Kopecky
Idoox