Re: PC--What is it good for?

On Mon, 17 Dec 2007 16:44:56 -0800, archmage@[EMAIL PROTECTED]
 (Nate Edel) wrote:
>In rec.arts.sf.written Jasper Janssen <jasper@[EMAIL PROTECTED]
> wrote:
>> On Thu, 13 Dec 2007 13:35:27 -0800, archmage@[EMAIL PROTECTED]
 (Nate Edel)
wrote:
>> >Heck, from what I can see, people don't want to even deal with
properly
>> >stopping external USB devices before unplugging them, and that's no
cash
>> >cost, just inconvenience.
>>
>> And there's no reason whatsoever for it to be necessary, either.
Writeback
>> versus write-through caching schemes aren't *that* different in
>> performance, mostly. Most USB sticks and card readers have activity
LEDs,
>> jsut like floppy drives used to have. Don't pull while light is
fla****ng.
>
>Writeback vs. write through makes a huge difference when the issue is
>batching up metadata writes vs. making everything synchronous.  That's
>especially true with disk with its big difference in seek time vs. write
>throughput, but somewhat noticeable even with flash. 

I'm not sure you should be using an external disk for applications where
you'd be regularly writing very small chunks of data, anyway. It's not the
typical usage scenario for a USB stick, that's for sure. Or at least it
wasn't prior to U3/****tableApps & co.

If the cache is inside the controller on the USB key, it will of course
light the read/write led while any data is waiting in the cache to be
written. I don't think there's an API that allows it to do the same for a
writeback cache in the PC itself, but it wouldn't be *that* hard to
implement.

Jasper