On Mon, 5 Dec 2005 [EMAIL PROTECTED] wrote: > >> 1. What is minimal time from plug eg.USB pendrive to moment when you can > >> mount it? > > > >It depends a little on the device. Usually the minimal time is under a > >second. But the default time is set to 5 seconds, because some devices > >(Apple iPods, for instance) need the extra delay. > > > > "Usually" under Linux? Does USB specificatin say anyting about it?
The USB specification does not say much. If anything, it gives a minimum time of 10 ms. But that's not really meaningful. > Do you have any documents from Apple where it stays so? No. Only reports from users whose devices don't work without the 5-second delay. I asked several of them if a shorter delay would be okay, but they never responded. > >> How can I optimize it? Now on my kernel 2.6.11 and Pendrive > >> Kingston TRaveler 512MB it takes about few (5-6) seconds. > > > >You can set the extra delay to any number of seconds by adding a line to > >/etc/modprobe.conf. For example, to eliminate it entirely (set it to 0), > >add a line saying > > > >options usb-storage delay_use=0 > > > > no results Did you rmmod the usb-storage driver, so that when it was reloaded it would see the new setting? > >> Does mount time depends on device storage amount? > > > >Not unless you have a pendrive with more than about 10 GB of storage. :-) > > > > > So it depends :-) but for low sizes it is not so big difference. But eg. > mounting USB HDisks 100GB?? That would probably take some time, whether it was a USB disk or IDE. No doubt it would also depend on the drive's speed. > Do you know where I can found description how Linux "mounting" process is > going on? No, sorry. > >> 2. Linux requiring more memory if I plug more USB devices at the same time? > > > >Yes. Not much memory just to plug in a device, maybe one or two > >thousand bytes. That\'s just an estimate; I haven\'t actually tried to > >measure it. Mounting a device takes more. > > > > How much more? How much memory is needed to mount 1GB. It is linear > dependency? (eg.1GB data -> 1kb for filesystem) I don't know how much memory. It probably is linear, though. > >> How does it work? > > > >How does what work? > > > > I mean mounting process :-) I don't know. You can try asking on the Linux Kernel Mailing List, or try reading one of the books about the internal operation of Unix. Alan Stern ------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Do you grep through log files for problems? Stop! Download the new AJAX search engine that makes searching your log files as easy as surfing the web. DOWNLOAD SPLUNK! http://ads.osdn.com/?ad_id=7637&alloc_id=16865&op=click _______________________________________________ Linux-usb-users@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-users
