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Minor
Description
Currently size is set like:
current_size = 0;
desired_size = (ib_int64_t)size + (((ib_int64_t)size_high) << 32);
#ifdef HAVE_POSIX_FALLOCATE
if (srv_use_posix_fallocate) {
if (posix_fallocate(file, current_size, desired_size) == -1) {
Thus file size is always extended from offset 0 to desired offset. This is clearly slower than doing
posix_fallocate(real_current_size, desired_size)
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revno: 4008
branch nick: 10.0
message:
MDEV-5746: Slow file extend when innodb_use_fallocate=1 and SSD
file storage.
Analysis: posix_fallocate was called using 0 as offset and len as
desired size. This is not optimal for SSDs.
Fix: Call posix_fallocate with correct offset i.e. current file size
and extend the file from there len bytes.
revno: 4098
message:
MDEV-5746: Slow file extend when innodb_use_fallocate=1 and SSDfile storage.
Analysis: posix_fallocate was called using 0 as offset and len as
desired size. This is not optimal for SSDs.
Fix: Call posix_fallocate with correct offset i.e. current file size
and extend the file from there len bytes.