Revision 859dd55d91d977090efbba15c7dfc82e7ed774ef authored by Ulf Hansson on 13 December 2011, 15:52:00 UTC, committed by Russell King on 20 January 2012, 00:00:54 UTC
A significant increase (10-20%) in performance throughput for USB mass storage is the reason for incrementing the value. By some reason the USB driver allocates buffers which requires a scattergather list to contain a lot more than 16 elements to get optimal performance. This change sets the maximum elements to 128. Tests with large reads and large writes (100 MiB) show that the throughput increase is significant for write (10% for this test) but not for read. Tests are run on a Linux host with ext4 FS on the gadget mass storage device. The sg-len still exceeds 16 for the read tests but the performance gain is low or nothing. Tested-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Per Forlin <per.forlin@stericsson.com> Signed-off-by: Ulf Hansson <ulf.hansson@stericsson.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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| File | Mode | Size |
|---|---|---|
| Documentation | ||
| arch | ||
| block | ||
| crypto | ||
| drivers | ||
| firmware | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .gitignore | -rw-r--r-- | 1014 bytes |
| .mailmap | -rw-r--r-- | 4.2 KB |
| COPYING | -rw-r--r-- | 18.3 KB |
| CREDITS | -rw-r--r-- | 92.8 KB |
| Kbuild | -rw-r--r-- | 2.5 KB |
| Kconfig | -rw-r--r-- | 252 bytes |
| MAINTAINERS | -rw-r--r-- | 202.0 KB |
| Makefile | -rw-r--r-- | 52.2 KB |
| README | -rw-r--r-- | 17.0 KB |
| REPORTING-BUGS | -rw-r--r-- | 3.3 KB |
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