Re: The anchor patch critique
Oliver Neukum <[email protected]>
| Newsgroups | gmane.linux.usb.devel |
|---|---|
| Message-ID | <[email protected]> |
Am Mittwoch, 6. Juni 2007 schrieb Pete Zaitcev: > So, you add 24 bytes to all URBs, which are... not very thin, to be sure. > Last time I counted they were 152 bytes apiece. Still, a 15% increase. > I know you're a good algorithmist, are you sure you don't have any ideas? > > The naive approach is to have anchor elements out of line... In a slab, > since they are fixed-sized. What do you think? 1. We can reorder elements a bit. The are taking padding in the 64 bit case 2. We can merge struct usb_device* and pipe into struct endpoint* 3. We could move to a union for the control and iso/int fields Why do you care that much about the size of struct urb? There are a few hundred of these structures at most at any given time. I think we gain more in memory usage if we make using URBs easier, shrinking drivers' code. Regards Oliver ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ [email protected] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel