Originally Posted by qole

I wonder if this would fix the problems people have been having trying to decompress the Easy Debian image. Decompressing a 2GB image in MyDocs basically brings the system to its knees and takes over an hour.

I filed a bug and nobody had any idea what was wrong...

Originally Posted by joerg_rw

That's not entirely correct. flash memory has massive penalty on writing randomly to different erase pages. I planned to share a link here, but have to realize I can't find the one good one. Google might help, or ask shadowJK on #maemo IRC. Basically the point is - depending on number of buffers in MMC controller - the writing to a different erase page (wich are sized like e.g 128kb) makes the controller erase a flash-page and write the dirty internal buffer to flash, then read back to buffer the new page addressed, and finally modifies the content of buffer according to the pending IO. So for a sequence like write to 0x10000, 0x50000, 0xB0000 it makes almost no difference if the individual write IO is for 1 byte or 50kB - it's the erasing and rewriting of a whole page that takes xx milliseconds, while IO to the same erase page actually only modifies the RAM buffer in controller and takes no time at all.


AFAIK a lot of elementary stuff already is mlocked, e.g rtcom-dialer-ui

What we really need is maybe a scheduler (plus kswapd) tailored to fit the exact operation mode and capabilities of the particular flash controller

/j

Originally Posted by nightfire

Hey everyone,

I've been using my phone as a wireless media server for friends (with Samba + wifi hotspot). While it worked brilliantly for reads, writes were causing all kinds of weird issues, and absolutely destroyed interactivity on the phone itself.

Later, while copying several 400mb files from internal storage to my SD card, it actually froze, and rebooted. I suspect dsme was swapped out and couldn't respond quickly enough to avoid the watchdog.

Originally Posted by akpoff

Your work on improving interactivity is much appreciated but I want to make sure we're not missing an important point as well -- you're using your N900 as a wireless media server with Samba and copying hundreds of megabytes at a time internally.

This behavior deserves recognition for going above the call of duty to prove the N900 is indeed a pocket computer.

Originally Posted by nightfire

The thing is, I suspect the I/O buffer on most MicroSD cards is big enough that we don't routinely hit the situation of distributed writes causing excessive erases, because for me the streaming performance wasn't affected at all.

Originally Posted by lma

On the subject of swap, do take a look at the ramzez and Diablo Turbo threads. On Diablo at least, ramzswap is the single most effective way to improve responsiveness when memory-starved (which is pretty much always if you're actually using the device).

Originally Posted by Creamy Goodness

you can adjust most of these settings from swappolube, but its missing the

Code:

/proc/sys/vm/min_free_kbytes 
/sys/block/mmcblk0/queue/nr_requests
/sys/block/mmcblk1/queue/nr_requests

why couldn't you look yourself?