The sbromwich series of kernels are the kernels I run on my phone with all current webos-internals testing patches applied, plus my patches, plus my kernel configuration.

The kernels are currently available at http://ipkg.preware.org/feeds/webos-kernels/testing/1.4.1.1/ and can be added using any standard package manager in the standard format (deducing this is left as an exercise for the reader).

Patches applied for 1.4.1-25 ("adric")

wfi instruction on prcm fail removed to validate if this is a regression causing battery drain.

Patches applied for 1.4.1-24 ("jangofett")

Reduce number of scheduling calls made to try to reduce battery drain. This may have an adverse affect on wake from suspend.

Patches applied for 1.4.1-23 ("bobafett")

Debug settings removed from default kernel build.
Compile kernel with explicit cortex-a8 tuning flags for gcc.
Tweak prcm power manager to more explicitly wait for power set calls to return, remove debug cruft, and add Wait For Interrupt instruction if a prcm setting attempt fails.
Enable preempt kernel.

Known problems

Pre can take some extra time to respond to certain activities, especially when waking up; lags of up to 2 seconds can be experienced on wakeup. The alternative is a reboot, which will take even longer.

Improvements

User interactivity latency should be lower (time to respond to keypresses, etc).
Fewer powerd wakeups allowing the system to sleep longer.

Warnings

My patch makes the kernel boot at 800MHz. Run this kernel at your own risk. Not compliant with point 6 of http://forums.precentral.net/webos-internals/241355-next-generation-kernel-development-packaging.html .
anticipatory io scheduler recommended.
Install SmartReflex patches at your own risk. SmartReflex is not expected to work.
Some users have reported increased battery usage when running this kernel.

Settings used with this kernel

I use the following event.d script:

description "Local tuning modes" start on stopped finish stop on runlevel [!2] console none script # Set governor echo "performance" > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor # Set min frequency echo 250000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq # Set max frequency echo 800000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq # Set io scheduler to anticipatory echo anticipatory > /sys/block/mmcblk0/queue/scheduler # Powertop Suggestion: increase the VM dirty writeback time from 5.00 to 15 # seconds. 0.50s works better on flash as it has slow writes. Needs more testing. echo 50 > /proc/sys/vm/dirty_writeback_centisecs # Use YeaH TCP as it's fairer over wireless echo yeah > /proc/sys/net/ipv4/tcp_congestion_control # Don't cache route metrics since we're mobile echo 1 > /proc/sys/net/ipv4/tcp_no_metrics_save # Ramp up the tx/rx network buffers in case we get bursty echo 1048576 > /proc/sys/net/core/rmem_max echo 1048576 > /proc/sys/net/core/wmem_max echo 3000 > /proc/sys/net/core/netdev_max_backlog nohup /usr/local/bin/pt.pl > /dev/null 2>&1 & /usr/sbin/iptables -D INPUT -i eth0 -p tcp --sport 5222 -s 205.140.203.0/24 -j ACCEPT > /dev/null 2>&1 /usr/sbin/iptables -I INPUT -i eth0 -p tcp --sport 5222 -s 205.140.203.0/24 -j ACCEPT echo 5 > /proc/sys/vm/laptop_mode end script # end of file

In addition, I am using my naive perl scheduler at http://www.fop.ns.ca/pre/pt/pt.pl to manage the CPU frequency.

Application:SBromwichKernel

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