Increase BUFFSIZE to handle very large /proc/stat files
We read /proc/stat using a statically sized buffer. This was increased to 64kB in 2005 via commit 777fcd3c "/proc/stat for 1024 CPUs".
Unfortunately in 2020, 1024 CPUs is not enough for anyone. I have a large machine where /proc/stat is 74kB, and vmstat gives incorrect output.
Double the buffer to 128kB in the confidence that 2048 CPUs is actually enough for anyone.
Signed-off-by: Anton Blanchard anton@ozlabs.org