Re: patch to shift memory allocations to usb_alloc_urb()
Oliver Neukum <[email protected]>
| Newsgroups | gmane.linux.usb.devel |
|---|---|
| Message-ID | <[email protected]> |
Am Sonntag, 1. Juli 2007 schrieb Matthew Dharm: > On Sun, Jul 01, 2007 at 11:00:43AM +0200, Oliver Neukum wrote: > > My goals are: > > > > - guarantee the storage driver a fallback path without memory allocation > > What about avoiding allocation of memory during a usb-storage transfer > completely? IIRC Alan computed the worst case memory requirements and for permanently allocated memory it was bad. > Does anyone know if the SCSI core actually follows the sg_tablesize > parameter in the struct scsi_host_template ? Right now, it's set to > SG_ALL, which means "unlimited number of sg elements", but any other > non-zero value is supposed to be the maximum number of segments that the > SCSI core sends to usb-storage. It seems to me that this is the key parameter determining the throughput of the storage driver. 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