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authorLen Brown <len.brown@intel.com>2008-10-22 23:57:26 -0400
committerLen Brown <len.brown@intel.com>2008-10-23 00:11:07 -0400
commit057316cc6a5b521b332a1d7ccc871cd60c904c74 (patch)
tree4333e608da237c73ff69b10878025cca96dcb4c8 /Documentation/block
parent3e2dab9a1c2deb03c311eb3f83466009147ed4d3 (diff)
parent2515ddc6db8eb49a79f0fe5e67ff09ac7c81eab4 (diff)
Merge branch 'linus' into test
Conflicts: MAINTAINERS arch/x86/kernel/acpi/boot.c arch/x86/kernel/acpi/sleep.c drivers/acpi/Kconfig drivers/pnp/Makefile drivers/pnp/quirks.c Signed-off-by: Len Brown <len.brown@intel.com>
Diffstat (limited to 'Documentation/block')
-rw-r--r--Documentation/block/data-integrity.txt4
-rw-r--r--Documentation/block/deadline-iosched.txt14
2 files changed, 12 insertions, 6 deletions
diff --git a/Documentation/block/data-integrity.txt b/Documentation/block/data-integrity.txt
index e9dc8d86adc..e8ca040ba2c 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.
retrieve the tag buffer using bio_integrity_get_tag().
-6.3 PASSING EXISTING INTEGRITY METADATA
+5.3 PASSING EXISTING INTEGRITY METADATA
Filesystems that either generate their own integrity metadata or
are capable of transferring IMD from user space can use the
@@ -283,7 +283,7 @@ will require extra work due to the application tag.
integrity upon completion.
-6.4 REGISTERING A BLOCK DEVICE AS CAPABLE OF EXCHANGING INTEGRITY
+5.4 REGISTERING A BLOCK DEVICE AS CAPABLE OF EXCHANGING INTEGRITY
METADATA
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 c23cab13c3d..72576769e0f 100644
--- a/Documentation/block/deadline-iosched.txt
+++ b/Documentation/block/deadline-iosched.txt
@@ -30,12 +30,18 @@ write_expire (in ms)
Similar to read_expire mentioned above, but for writes.
-fifo_batch
+fifo_batch (number of requests)
----------
-When a read request expires its deadline, we must move some requests from
-the sorted io scheduler list to the block device dispatch queue. fifo_batch
-controls how many requests we move.
+Requests are grouped into ``batches'' of a particular data direction (read or
+write) which are serviced in increasing sector order. To limit extra seeking,
+deadline expiries are only checked between batches. fifo_batch controls the
+maximum number of requests per batch.
+
+This parameter tunes the balance between per-request latency and aggregate
+throughput. When low latency is the primary concern, smaller is better (where
+a value of 1 yields first-come first-served behaviour). Increasing fifo_batch
+generally improves throughput, at the cost of latency variation.
writes_starved (number of dispatches)