| sysfs-block (07c9093c429361dd405499b1e433e4170b81551f) | sysfs-block (8b0551a74b4a9396a7f6ddb0c5f6f3c8465e9d45) |
|---|---|
| 1What: /sys/block/<disk>/alignment_offset 2Date: April 2009 3Contact: Martin K. Petersen <martin.petersen@oracle.com> 4Description: 5 Storage devices may report a physical block size that is 6 bigger than the logical block size (for instance a drive 7 with 4KB physical sectors exposing 512-byte logical 8 blocks to the operating system). This parameter --- 228 unchanged lines hidden (view full) --- 237 chunk size. A properly aligned multiple of 238 minimum_io_size is the preferred request size for 239 workloads where a high number of I/O operations is 240 desired. 241 242 243What: /sys/block/<disk>/queue/nomerges 244Date: January 2010 | 1What: /sys/block/<disk>/alignment_offset 2Date: April 2009 3Contact: Martin K. Petersen <martin.petersen@oracle.com> 4Description: 5 Storage devices may report a physical block size that is 6 bigger than the logical block size (for instance a drive 7 with 4KB physical sectors exposing 512-byte logical 8 blocks to the operating system). This parameter --- 228 unchanged lines hidden (view full) --- 237 chunk size. A properly aligned multiple of 238 minimum_io_size is the preferred request size for 239 workloads where a high number of I/O operations is 240 desired. 241 242 243What: /sys/block/<disk>/queue/nomerges 244Date: January 2010 |
| 245Contact: | 245Contact: linux-block@vger.kernel.org |
| 246Description: 247 Standard I/O elevator operations include attempts to 248 merge contiguous I/Os. For known random I/O loads these 249 attempts will always fail and result in extra cycles 250 being spent in the kernel. This allows one to turn off 251 this behavior on one of two ways: When set to 1, complex 252 merge checks are disabled, but the simple one-shot merges 253 with the previous I/O request are enabled. When set to 2, --- 114 unchanged lines hidden --- | 246Description: 247 Standard I/O elevator operations include attempts to 248 merge contiguous I/Os. For known random I/O loads these 249 attempts will always fail and result in extra cycles 250 being spent in the kernel. This allows one to turn off 251 this behavior on one of two ways: When set to 1, complex 252 merge checks are disabled, but the simple one-shot merges 253 with the previous I/O request are enabled. When set to 2, --- 114 unchanged lines hidden --- |