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Diffstat (limited to 'Documentation/device-mapper/dm-crypt.txt')
| -rw-r--r-- | Documentation/device-mapper/dm-crypt.txt | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/Documentation/device-mapper/dm-crypt.txt b/Documentation/device-mapper/dm-crypt.txt index c81839b52c4d..ad697781f9ac 100644 --- a/Documentation/device-mapper/dm-crypt.txt +++ b/Documentation/device-mapper/dm-crypt.txt @@ -51,7 +51,7 @@ Parameters: <cipher> <key> <iv_offset> <device path> \ Otherwise #opt_params is the number of following arguments. Example of optional parameters section: - 1 allow_discards + 3 allow_discards same_cpu_crypt submit_from_crypt_cpus allow_discards Block discard requests (a.k.a. TRIM) are passed through the crypt device. @@ -63,6 +63,19 @@ allow_discards used space etc.) if the discarded blocks can be located easily on the device later. +same_cpu_crypt + Perform encryption using the same cpu that IO was submitted on. + The default is to use an unbound workqueue so that encryption work + is automatically balanced between available CPUs. + +submit_from_crypt_cpus + Disable offloading writes to a separate thread after encryption. + There are some situations where offloading write bios from the + encryption threads to a single thread degrades performance + significantly. The default is to offload write bios to the same + thread because it benefits CFQ to have writes submitted using the + same context. + Example scripts =============== LUKS (Linux Unified Key Setup) is now the preferred way to set up disk |