LOLi 047187c1bd Fix size inflation in spa_get_worst_case_asize() ... When we try assign a new transaction to a TXG we must know beforehand if there is sufficient free space on disk. This is to decide, in dmu_tx_assign(), if we should reject the TX with ENOSPC. We rely on spa_get_worst_case_asize() to inflate the size of our logical writes by a factor of spa_asize_inflation which is calculated as: (VDEV_RAIDZ_MAXPARITY + 1) * SPA_DVAS_PER_BP * 2 == 24 The problem with the current implementation is that we don't take into account what happens with very small writes on VDEVs with large physical block sizes. Consider the case of writes to a dataset with recordsize=512, copies=3 on a VDEV with ashift=13 (usually SSD with 8K block size): every logical IO will end up allocating 3 * 8K = 24K on disk, so 512 bytes multiplied by 48, which is double the size we account for. If we allow this kind of writes to be assigned a TX it is possible, when the pool is almost full, to trigger an allocation failure (ENOSPC) in the ZIO pipeline, which will in turn result in the whole pool being suspended. The bug is fixed by using, in spa_get_worst_case_asize(), the MAX() value chosen between the logical io size from zfs_write() and the maximum physical block size used among our VDEVs. Reviewed by: Matthew Ahrens <mahrens@delphix.com> Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: loli10K <ezomori.nozomu@gmail.com> Closes #5941		2017-04-10 15:28:21 -07:00
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cmd	codebase style improvements for OpenZFS 6459 port	2017-01-22 13:25:40 -08:00
include	OpenZFS 7404 - rootpool_007_neg, bootfs_006_pos and bootfs_008_neg tests fail with the loader project bits	2017-04-07 14:18:19 -07:00
tests	Fix size inflation in spa_get_worst_case_asize()	2017-04-10 15:28:21 -07:00
Makefile.am	Add the ZFS Test Suite	2016-03-16 13:46:16 -07:00