Ext4 Developer Interlock Call
October 29, 2007: Meeting Minutes
Attendees: Mingming Cao, Aneesh Veetil, Coly Li, Takashi Sato, Jean
Pierre Dion, Avantika Mathur
We had a short meeting today.
Fragmentation issues with Delayed Allocation
- without delalloc the reservation window is discarded at file close
time. With delalloc enabled some pages are still dirty in cache so we
can't discard the reservation right at file close. Aneesh is looking
into when to call ext4_discard_reservation() when delalloc is enabled.
If the reservation is discarded too early, there could be file
fragmentation, if it is discarded late the files could be spread across
the filesystem.
- This discussion will be continued on the mailing list.
- Takashi is planning to merge his online defragmentation patches into
ext4-git tree. He recently ran into a new data corruption problem.
Once he fixes this problem he will send out the patches.
- Large files: Aneesh is planning to do some more needed testing.
- Today Coly will be sendng his directory inode reservation patches
which fix readdir performance issues. These patches do not modify
on-disk format; and have not yet been performance tested.
- Mingming will add Jean Noel's new i_version patches to the queue today