freebsd-dev/module/zcommon
Matthew Ahrens f1512ee61e Illumos 5027 - zfs large block support
5027 zfs large block support
Reviewed by: Alek Pinchuk <pinchuk.alek@gmail.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Josef 'Jeff' Sipek <josef.sipek@nexenta.com>
Reviewed by: Richard Elling <richard.elling@richardelling.com>
Reviewed by: Saso Kiselkov <skiselkov.ml@gmail.com>
Reviewed by: Brian Behlendorf <behlendorf1@llnl.gov>
Approved by: Dan McDonald <danmcd@omniti.com>

References:
  https://www.illumos.org/issues/5027
  https://github.com/illumos/illumos-gate/commit/b515258

Porting Notes:

* Included in this patch is a tiny ISP2() cleanup in zio_init() from
Illumos 5255.

* Unlike the upstream Illumos commit this patch does not impose an
arbitrary 128K block size limit on volumes.  Volumes, like filesystems,
are limited by the zfs_max_recordsize=1M module option.

* By default the maximum record size is limited to 1M by the module
option zfs_max_recordsize.  This value may be safely increased up to
16M which is the largest block size supported by the on-disk format.
At the moment, 1M blocks clearly offer a significant performance
improvement but the benefits of going beyond this for the majority
of workloads are less clear.

* The illumos version of this patch increased DMU_MAX_ACCESS to 32M.
This was determined not to be large enough when using 16M blocks
because the zfs_make_xattrdir() function will fail (EFBIG) when
assigning a TX.  This was immediately observed under Linux because
all newly created files must have a security xattr created and
that was failing.  Therefore, we've set DMU_MAX_ACCESS to 64M.

* On 32-bit platforms a hard limit of 1M is set for blocks due
to the limited virtual address space.  We should be able to relax
this one the ABD patches are merged.

Ported-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #354
2015-05-11 12:23:16 -07:00
..
Makefile.in
zfs_comutil.c Illumos #2882, #2883, #2900 2013-09-04 15:49:00 -07:00
zfs_deleg.c Change ASSERT(!"...") to cmn_err(CE_PANIC, ...) 2015-03-03 13:22:21 -08:00
zfs_fletcher.c
zfs_namecheck.c Illumos 4368, 4369. 2014-07-29 10:55:29 -07:00
zfs_prop.c Illumos 5027 - zfs large block support 2015-05-11 12:23:16 -07:00
zfs_uio.c cstyle: Resolve C style issues 2013-12-18 16:46:35 -08:00
zpool_prop.c Illumos 5027 - zfs large block support 2015-05-11 12:23:16 -07:00
zprop_common.c Change KM_PUSHPAGE -> KM_SLEEP 2015-01-16 14:41:26 -08:00