On Wed, Aug 13, 2025 at 02:45:28PM +0100, John Garry wrote: > On 10/08/2025 14:42, Ojaswin Mujoo wrote: > > From: "Ritesh Harjani (IBM)"<ritesh.list@xxxxxxxxx> > > > > Brute force all possible blocksize clustersize combination on a bigalloc > > filesystem for stressing atomic write using fio data crc verifier. We run > > multiple threads in parallel with each job writing to its own file. The > > parallel jobs running on a constrained filesystem size ensure that we > > stress the ext4 allocator to allocate contiguous extents. > > > > This test might do overlapping atomic writes but that should be okay > > since overlapping parallel hardware atomic writes don't cause tearing as > > long as io size is the same for all writes. > > > > Signed-off-by: Ritesh Harjani (IBM)<ritesh.list@xxxxxxxxx> > > Reviewed-by: Darrick J. Wong<djwong@xxxxxxxxxx> > > Signed-off-by: Ojaswin Mujoo<ojaswin@xxxxxxxxxxxxx> > > --- > > tests/ext4/062 | 176 +++++++++++++++++++++++++++++++++++++++++++++ > > tests/ext4/062.out | 2 + > > 2 files changed, 178 insertions(+) > > create mode 100755 tests/ext4/062 > > create mode 100644 tests/ext4/062.out > > Is the only difference to 061 that we have multiple files (and not a single > file)? Hey John, Yes these 2 tests are similar however 061 uses fallocate=native + _scratch_mkfs_ext4 to test whether atomic writes on preallocated file via multiple threads works correctly. The 062 uses fallocate=truncate + _scratch_mkfs_sized 360MB + 'multiple jobs each writing to a different file' to ensure we are extensively stressing the allocation logic in low space scenarios. Regards, ojaswin > > Thanks, > John
