Originally Posted by don_falcone

Indeed 32 may be too little. Otherwise i couldn't explain memory read-only errors during a dpkg run.

Originally Posted by vi_

Code:

echo 3 > /proc/sys/vm/dirty_ratio
echo 3 > /proc/sys/vm/dirty_background_ratio
echo 100 > /proc/sys/vm/dirty_writeback_centisecs 
echo 100 > /proc/sys/vm/dirty_expire_centisecs 
echo 1024 > /proc/sys/vm/min_free_kbytes 
echo 95 > /proc/sys/vm/swappiness 
echo 250 > /proc/sys/vm/vfs_cache_pressure 
echo 0 > /proc/sys/vm/page-cluster
echo 512 > /sys/block/mmcblk0/queue/nr_requests
echo 512 > /sys/block/mmcblk1/queue/nr_requests
echo 0 > /sys/block/mmcblk0/queue/iosched/slice_idle
echo 0 > /sys/block/mmcblk1/queue/iosched/slice_idle
echo 16 > /sys/block/mmcblk0/queue/iosched/quantum
echo 16 > /sys/block/mmcblk1/queue/iosched/quantum
echo 64 > /sys/block/mmcblk0/queue/iosched/fifo_expire_sync
echo 64 > /sys/block/mmcblk1/queue/iosched/fifo_expire_sync
echo 64 > /sys/block/mmcblk0/queue/iosched/fifo_expire_async
echo 64 > /sys/block/mmcblk1/queue/iosched/fifo_expire_async

Try for yourself, report back.

Originally Posted by vi_

Not really such a great idea, what if someone is using uSD but not ramz and wants swappolube settings?

Originally Posted by vi_

Finally I would not be so hasty to add this to your start up unless you are comfortable with using a rescue console to undo what may go wrong.

Originally Posted by zimon

Where did you get iostat for N900?
dpkg --search `which iostat`

Edit: ah, apt-cache search iostat
-> sysstat

Originally Posted by mr_jrt

This ocurred to me as well. Always best to aim to be a good neighbour
Yes, good neighbours.

I propose then that swapset will have a set of override settings it will apply only when compcache is active. The trick will be managing to convince them to apply after swappolube's /etc/event.d/tuning gets executed. Hopefully upstart has dependencies in there somewhere.
Yes, it has. Just use
start on stopped tuning
This will start your script after 'tuning' script has stopped its activity.
We may use stopped here, as it terminates after setting its values. Otherwise just use
start on started tuning
and wait a few seconds.

There is also something like "signal" or "emit" afairc.

I'm thinking a set of defaults as given in this thread, with another set of overrides in /etc/default/swapset, i.e.

Code:

# Size of cache in KB
#COMPCACHE_SIZE	=	"65536"

# Swap priorities
#PRIORITY_COMPCACHE	=	"15"
#PRIORITY_EXTERNAL	=	"10"
#PRIORITY_INTERNAL	=	"0"

# Timeout for device node to be ready in seconds
#COMPCACHE_TIMEOUT	=	"10"  

# VM tuning for compcache
DEFAULT_COMPCACHE_TUNING	=	"true"
#vm_dirty_ratio			=	"3"
#vm_dirty_background_ratio	=	"3"
#vm_dirty_writeback_centisecs	=	"100"
#vm_dirty_expire_centisecs	=	"100"
#vm_min_free_kbytes	=	"32"
#vm_swappiness		=	"95"
#vm_vfs_cache_pressure	=	"200"
#vm_page-cluster	=	"0"
#int_nr_requests	=	"4000"
#ext_nr_requests	=	"4000"

The next item I wanted to add to swapset before my hiatus was a semaphore to signal the device booted OK to prevent reboot loops. Something simple, like an empty file when it starts that it then removes at the end. If it finds the file on boot, don't apply the settings and report to the user. Should hopefully make things safer.
Nice idea, like power kernel does maybe.

Anyway, I'll get on this once I get a few minutes and:

• Add boot semaphore
• Fix timeout bug reported by peterleinchen
• Fix bug reported by alfred, which IIRC, was due to having a SD card active without a swap partition on it (wish this forum saved sent PMs! - Incidentally, please email me bugs for exactly this reason)
  this forum saves sent PMs, just enable it under your preferences
  
• Pull in override params from config file /etc/default/swapset
• Override swappolube settings when compcache is active

That everything?
More or less yes.
I found another bug, I think:
if [ $compcache_succeeded ]
always is true, use
if [ -e /dev/ramzswap0 -a -z "$(grep ramzswap0 < /proc/swaps)" ]
instead

Originally Posted by vi_

yeah

However if you look on the wiki page you will find the 64MB settings that work like a champ.