Thread: 256mb for installable aplications?? Am I awake or is this only a bad dream?
View Single Post
fanoush is offline fanoush
2009-10-01 , 12:35
Posts: 2,152 | Thanked: 1,490 times | Joined on Jan 2006 @ Czech Republic
#24
Originally Posted by attila77 View Post
No, I didn't mean the physical flash, but the process - compression does not necessarily slow you down (if you can (de)compress faster than you can read/write, you're actually better off).
at least it eats a lot of CPU which is bad if the CPU time is needed somwhere else. Maybe with N900 cpu being faster this is not such big issue but with 700 and N8x0 the CPU hit is IMO significant. Also CPU usage = battery drain.

Originally Posted by attila77 View Post
When I discussed some loopfile-related projects with Nokia folks it has been suggested that they *did* benchmark it and the internal flash was significantly slower. I would reference it, but it was in an off-list reply so for now you will have to take my word for it unless the original author chimes in
would like to see some data because I don't believe it too. Both with 770 and N8x0 root on SD/MMC is faster than jffs2 in my experience. There are some specific use cases where it is slower (like using sqlite which does fsync after each database write see https://bugs.maemo.org/show_bug.cgi?id=1842#c13 ) but overall it feels faster to me. Even with swapping it shouldn't be so bad. As for benchmarks simple read only or write only tests should be definitely faster with sd/mmc. I never did some concurrent read/write benchmark but can see that this may indeed be a problem. But how often we see concurrent read and write except swapping?
Originally Posted by attila77 View Post
Try starting a larger Qt app on a cloned setup and you'll se the problem - it will read the Qt libs from the card and as it takes up memory start to swap on the same card, resulting in abysmal startup times and several seconds of total unresponsiveness.
swap is slow in any case. I don't think actively using more memory than available is good idea in any case. And BTW one can swap to (or boot from) other SD/MMC card if this is really a bottleneck in real life.

Originally Posted by attila77 View Post
This is also one of the main reasons Qt and Python are not optified in Fremantle - so they would not be on the same device as the swap.
Oh really? Hmm, I know for N900 they configured 756 MB for swap, this also feels very strange to me with only 256MB of real RAM. Planning to use so much swap feels somehow wrong to me. Well we'll see once we have real devices in our hands. I definitely plan to boot from something else than internal NAND.
__________________
Newbies click here before posting. Thanks.

If you really need to PM me with troubleshooting question please consider posting it to the forum instead. It is OK to PM me a link to such post then. Thank you.
 

The Following 3 Users Say Thank You to fanoush For This Useful Post: