[FormerPalmOS]

Scott,

I've been studying the performance some more now with the modified XIP. The next low-hanging fruit is the number of files in the \windows directory. With no caching, when you access any file in the Windows directory (or when an application needs a DLL), WM loads the directory from flash, then starts at the top looking for what you need. It isn't stored alphabetically or anything - it's a straight sequential search. The average time of the search is directly related to the number of files in the directory. Once found, a file or module is copied from IMGFS, decompressed and loaded into the pagepool.

Now, you can increase the pagepool size to reduce thrashing within the pagepool, and I can increase the FAT and directory meta-data cache to speed up this overall process - but all is at the expense of memory.

As an alternative, it would be worthwhile to figure out what applications installed in your OEM folders could be installed to directories (\Program Files\{appname} for example) instead of to \windows. Manilla for example has tons of files loaded to \windows. Microsoft is guilty as well - there are a boatload of resources (bitmaps, .pngs, etc) all loaded to Windows.

Note - this also explains why a stripped ROM is so much faster - far fewer files to search through in the \Windows directory.

Also - for chefs - fewer apps go for smaller pagepool (6 would be fine for a totally stripped ROM). Loaded go for 12. Anything bigger than 12 and you are asking for memory problems.

Oh - Scott, BTW - nuke HTC_CM_Guardian from your OEM folders (I already killed it so I can't go searching for it to tell you where to remove it). THis file monitors and resets certain settings back to "carrier stock" - not sure which ones, but it is always resident taking up memory and I don't like that. No stability problems with it killed so-far.

BTW - two other memory hogs that can be killed are SIP_GTAPP and QuickGPS. The SIP app is responsible for the keyboard pop-up that allows you to change pop-up keyboards. It is possible to default SIP to one keyboard (I use Full QWERTY) then blow away the bootlauncher key that auto-starts it. QuickGPS can only be prevented from starting by killing the bootlauncher GPSAUX.DLL service - which also kills the underlying functionality QuickGPS brings. If you want fast locks, this is unfortunately a necessary evil. HTC could have easily split this into two programs so the resident one is much smaller - but they did not.