diff options
Diffstat (limited to 'Documentation/block')
-rw-r--r-- | Documentation/block/data-integrity.txt | 4 | ||||
-rw-r--r-- | Documentation/block/deadline-iosched.txt | 14 |
2 files changed, 12 insertions, 6 deletions
diff --git a/Documentation/block/data-integrity.txt b/Documentation/block/data-integrity.txt index e9dc8d86adc7..e8ca040ba2cf 100644 --- a/Documentation/block/data-integrity.txt +++ b/Documentation/block/data-integrity.txt | |||
@@ -246,7 +246,7 @@ will require extra work due to the application tag. | |||
246 | retrieve the tag buffer using bio_integrity_get_tag(). | 246 | retrieve the tag buffer using bio_integrity_get_tag(). |
247 | 247 | ||
248 | 248 | ||
249 | 6.3 PASSING EXISTING INTEGRITY METADATA | 249 | 5.3 PASSING EXISTING INTEGRITY METADATA |
250 | 250 | ||
251 | Filesystems that either generate their own integrity metadata or | 251 | Filesystems that either generate their own integrity metadata or |
252 | are capable of transferring IMD from user space can use the | 252 | are capable of transferring IMD from user space can use the |
@@ -283,7 +283,7 @@ will require extra work due to the application tag. | |||
283 | integrity upon completion. | 283 | integrity upon completion. |
284 | 284 | ||
285 | 285 | ||
286 | 6.4 REGISTERING A BLOCK DEVICE AS CAPABLE OF EXCHANGING INTEGRITY | 286 | 5.4 REGISTERING A BLOCK DEVICE AS CAPABLE OF EXCHANGING INTEGRITY |
287 | METADATA | 287 | METADATA |
288 | 288 | ||
289 | To enable integrity exchange on a block device the gendisk must be | 289 | To enable integrity exchange on a block device the gendisk must be |
diff --git a/Documentation/block/deadline-iosched.txt b/Documentation/block/deadline-iosched.txt index c23cab13c3d1..72576769e0f4 100644 --- a/Documentation/block/deadline-iosched.txt +++ b/Documentation/block/deadline-iosched.txt | |||
@@ -30,12 +30,18 @@ write_expire (in ms) | |||
30 | Similar to read_expire mentioned above, but for writes. | 30 | Similar to read_expire mentioned above, but for writes. |
31 | 31 | ||
32 | 32 | ||
33 | fifo_batch | 33 | fifo_batch (number of requests) |
34 | ---------- | 34 | ---------- |
35 | 35 | ||
36 | When a read request expires its deadline, we must move some requests from | 36 | Requests are grouped into ``batches'' of a particular data direction (read or |
37 | the sorted io scheduler list to the block device dispatch queue. fifo_batch | 37 | write) which are serviced in increasing sector order. To limit extra seeking, |
38 | controls how many requests we move. | 38 | deadline expiries are only checked between batches. fifo_batch controls the |
39 | maximum number of requests per batch. | ||
40 | |||
41 | This parameter tunes the balance between per-request latency and aggregate | ||
42 | throughput. When low latency is the primary concern, smaller is better (where | ||
43 | a value of 1 yields first-come first-served behaviour). Increasing fifo_batch | ||
44 | generally improves throughput, at the cost of latency variation. | ||
39 | 45 | ||
40 | 46 | ||
41 | writes_starved (number of dispatches) | 47 | writes_starved (number of dispatches) |