I have been mucking around with Debian Chroot and decided to see if things could be giving a speed boost by looking at what is booting on startup under OS2008, and found a bunch-o-stuff. I tried doing searches to see what all these do and whether they could be killed or not or other strategies to clear up some of our precious ram. Via the cpu monitor applet, here is a list of the top memory consumers on bootup on my Diablo based n800:

• hildon-desktop - 17MB - 5-8%: Needed - main desktop
• modest - 11MB - 0%: This is our email client. Oddly enough, I did not run it, nor do I believe I ever ran it. Why is it autobooting and consuming ~9% of my available ram? What is it doing?
• browserd - 11MB - 0%: Seems this is a daemon to render web pages for whatever apps. Microb needs it to run. There has to be a nice way to create a script that will run this, then launch microb, and then on closing microb kills this off again.
• osso-connectivity-ui-conndlgs - 10MB - 0%: Only thing I can find on this is it has to do with "Internet Connectivity Dialogs". Is it necessary for our wireless or can it be killed off and we would trade easy wifi modifications for 8% of our ram?
• hildon-input-method - 10MB - 0%: I would imagine this is the task responsible to bringing up the matchbox keyboard and whatnot. Highly needed for the n800.
• Xomap - 7MB - 0-1%: Our X Win Server. Definately needed.
• systemui - 5MB - 0%: Seems necessary - the xml file handles our tablet's state and whatnot.
• metalayer-crawler - 4MB - 0-alot%: This seems to be the task that scans the filesystem for media files, and has been the bane of a lot of folks CPU's in the past. While running searches on the forum, I have not actually seen any reports of any negative action that happens when this is disabled (and recovering 3% of our ram + CPU time).
• mediaplayer-engine - 4MB - 0%: Eh? Does this drive the internal media player only (you know, that program likely most do not use in favor of mplayer or the like) or does it have other purposes?
• matchbox-window-manager - 4MB - 0%: Our WM - needed.
• osso-media-server - 2MB - 0%: Yet another media related daemon?
• browserd - 2MB - 0%éjà vu - this same titled task running under another thread is consuming 11MB, bringing up the toll to 10% of total ram.
• sapwood server - 2MB - 0%: An image server - whatever that means.
• mission-control - 2MB - 0%: Best I could find, this is related to the built in IM program.
• telepathy-gabble - 2MB - 0%: And this too.. and bringing in telepathy-feed, brings the IM program up to 5MB (~4% of ram) which seems to always run, and no way to kill.
• e-addressbook-factory - 2MB - 0%: Eh? I'd imagine something to do with storing addresses (which I have none in my tablet).
• alarmd - 2MB - 0%: I really hope this 2MB isn't just responsible for the alarm clock (which doesn't seem to work anyways - but I digress).

Has there been any effort to document what these do (in common english) and whether they can be disabled and how? While everyone's use of the tablet likely is slightly different, I suspect the ROI on some of these would be less than acceptable for some.

metalayer-crawler is the only one that is reccomended to kill. If your SD card gets corrupted, it will run continuously and drain your battery in a couple hours. Maemo-control-services makes disabling it easy. Read that first (and backup), disabling some items will cause endless reboot, causing reflash.

To disable from command line:
update-rc.d metalayer-crawler remove

Unrelated: From your topic I thought this could help, but turns out it's not what you were talking about.

First, if you don't know what you're measuring, you're not likely to get useful measurements. With htop, I display M_SIZE, M_RESIDENT, and M_SHARE columns; I'm not sure which of these corresponds to whichever cpu monitor applet you're using, but I think it's M_RESIDENT.

• M_SIZE displays the total of all memory the process can address. Some of this may be in physical RAM, some may be swapped, and (I think) some may be memory mapped IO space.
• M_RESIDENT shows only physical RAM; it might seem natural to disable swap and use this as a memory use metric, but that's not clean either; some pages are shared among several processes, so they'll get multi-counted.
• M_SHARE shows the resident shared memory usage; so M_RESIDENT - M_SHARED (with no swap) gives the process specific usage, with no double-counting; unfortunately, this leaves the shared portion completely uncounted.

So one useful measurement for multiple processes, like browserd, is to count the shared memory once, and (resident - shared) for each process. This will still overcount somewhat, as some of that shared memory is shared by other processes, but it's a reasonable guess.
I'd include an obligatory reprimand for being to lazy to search for; but I'm not sure that it exists, as I'm too lazy to search for it. But I'll take a couple hipshots here...

(List shuffled to bring groups together.)

• Xomap - 7MB - 0-1%: Our X Win Server. Definately needed.

Except for N810, or with BT/USB keyboard; Debian has a usable text console. We could get that working, I'm sure...

• systemui - 5MB - 0%: Seems necessary - the xml file handles our tablet's state and whatnot.

Ditchable, but like X, probably wiser not. (One exception: powerlaunch, which exists as a standalone replacement. Probably doesn't save memory, though.)

• matchbox-window-manager - 4MB - 0%: Our WM - needed.

No; you can use lighter-weight options. FVWM2 uses about half the memory, just switching WMs...

• sapwood server - 2MB - 0%: An image server - whatever that means.

It serves up images for... the window manager! (Among others, but I think most other stuff will run anyway...) So switching WMs could mean ditching this, too.

• hildon-desktop - 17MB - 5-8%: Needed - main desktop

Not strictly speaking; if you're running an alternate WM, you could ditch this entirely. More savings. (This provides three windows -- home screen, navigator panel, and taskbar panel; you can replace the effects of these otherwise.)

• hildon-input-method - 10MB - 0%: I would imagine this is the task responsible to bringing up the matchbox keyboard and whatnot. Highly needed for the n800.

Not matchbox keyboard; this is for bringing up the hildon specific input methods. Again, if you're using a different WM, you might effectively ditch this. (This might prevent hildon apps from working, but I think they would work fine except the input methods...) You'd be replacing it with matchbox-keyboard, xvkbd, or some other, though; tanstaafl.

• browserd - 11MB - 0%: Seems this is a daemon to render web pages for whatever apps. Microb needs it to run. There has to be a nice way to create a script that will run this, then launch microb, and then on closing microb kills this off again.
• browserd - 2MB - 0%éjà vu - this same titled task running under another thread is consuming 11MB, bringing up the toll to 10% of total ram.

That'd cause slow startups, and not gain much, imho, but sure. I have a flock of browserd too, at 11760 kB RES, so that's why I think your tool's showing resident usage. They're closer to 3 MB in fact; and I've got two of the low-usage one too (which spawn the others).
[code]sudo /etc/init.d/tablet-browser-daemon start
browser --url=http://www.google.com/
sudo /etc/init.d/tablet-browser-daemon stop[code]

• e-addressbook-factory - 2MB - 0%: Eh? I'd imagine something to do with storing addresses (which I have none in my tablet).

Probably for modest.

• modest - 11MB - 0%: This is our email client. Oddly enough, I did not run it, nor do I believe I ever ran it. Why is it autobooting and consuming ~9% of my available ram? What is it doing?

It's dynamically linking to a number of libraries, mainly, which are mostly there anyway. Neither of these is running on mine, as I have yet to set email up on this install, so that's a little curious. But I'd guess it's doing no great harm overall. Could it be stopped without harm (if you don't use it for email...)? Sure.

• osso-connectivity-ui-conndlgs - 10MB - 0%: Only thing I can find on this is it has to do with "Internet Connectivity Dialogs". Is it necessary for our wireless or can it be killed off and we would trade easy wifi modifications for 8% of our ram?

Probably not necessary, if you make sure it autoconnects. But not sure.

• metalayer-crawler - 4MB - 0-alot%: This seems to be the task that scans the filesystem for media files, and has been the bane of a lot of folks CPU's in the past. While running searches on the forum, I have not actually seen any reports of any negative action that happens when this is disabled (and recovering 3% of our ram + CPU time).

Ax it. Unless you are using the supplied media player, and really want all media to be added to the library.

• mediaplayer-engine - 4MB - 0%: Eh? Does this drive the internal media player only (you know, that program likely most do not use in favor of mplayer or the like) or does it have other purposes?

Yes; it can be used by other players, and is by some. IIRC, canola uses it by default for audio, and mplayer for video.

• osso-media-server - 2MB - 0%: Yet another media related daemon?

I guess.

• alarmd - 2MB - 0%: I really hope this 2MB isn't just responsible for the alarm clock (which doesn't seem to work anyways - but I digress).

Only 296K of non-shared, though... (on mine) So it's not a big deal.

Thank you Benson for clarifying (and calming my internal OMG BBQ!!!11!) on ram usage - I'll have to someone look in more detail what exactly everything is using that is non-shared as well as the additional details on some of the tasks descriptions. One of my little side projects is seeing if I can hack together a lighter foundation to allow more ram to be used by active tasks, and this was most useful.