diff options
| -rw-r--r-- | cmd/ztest/ztest.c | 28 |
1 files changed, 15 insertions, 13 deletions
diff --git a/cmd/ztest/ztest.c b/cmd/ztest/ztest.c index dd5bf9894..ce748da18 100644 --- a/cmd/ztest/ztest.c +++ b/cmd/ztest/ztest.c @@ -5924,24 +5924,26 @@ ztest_fault_inject(ztest_ds_t *zd, uint64_t id) * on two different leaf devices, because ZFS can not * tolerate that (if maxfaults==1). * - * We divide each leaf into chunks of size - * (# leaves * SPA_MAXBLOCKSIZE * 4). Within each chunk - * there is a series of ranges to which we can inject errors. - * Each range can accept errors on only a single leaf vdev. - * The error injection ranges are separated by ranges - * which we will not inject errors on any device (DMZs). - * Each DMZ must be large enough such that a single block - * can not straddle it, so that a single block can not be - * a target in two different injection ranges (on different - * leaf vdevs). + * To achieve this we divide each leaf device into + * chunks of size (# leaves * SPA_MAXBLOCKSIZE * 4). + * Each chunk is further divided into error-injection + * ranges (can accept errors) and clear ranges (we do + * not inject errors in those). Each error-injection + * range can accept errors only for a single leaf vdev. + * Error-injection ranges are separated by clear ranges. * * For example, with 3 leaves, each chunk looks like: * 0 to 32M: injection range for leaf 0 - * 32M to 64M: DMZ - no injection allowed + * 32M to 64M: clear range - no injection allowed * 64M to 96M: injection range for leaf 1 - * 96M to 128M: DMZ - no injection allowed + * 96M to 128M: clear range - no injection allowed * 128M to 160M: injection range for leaf 2 - * 160M to 192M: DMZ - no injection allowed + * 160M to 192M: clear range - no injection allowed + * + * Each clear range must be large enough such that a + * single block cannot straddle it. This way a block + * can't be a target in two different injection ranges + * (on different leaf vdevs). */ offset = ztest_random(fsize / (leaves << bshift)) * (leaves << bshift) + (leaf << bshift) + |