Marc,
The pre-allocation is done with posix_fallocate which is O(1) on most filesystems - ie. the time to preallocate is independent of size.
Now, when posix_fallocate fails, the fallback is to physically write zeroes to the file which can be very time consuming.
What is the filesystem where the datadir is located and which distro is this. Seems like posix_fallocate is not supported on that platform.
Marc,
The pre-allocation is done with posix_fallocate which is O(1) on
most filesystems - ie. the time to preallocate is independent of
size.
Now, when posix_fallocate fails, the fallback is to physically
write zeroes to the file which can be very time consuming.
What is the filesystem where the datadir is located and which
distro is this. Seems like posix_fallocate is not supported on
that platform.