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Comment Easy problem to understand, hard to fix. (Score 1) 472

The problem is this: Let's say you do an action that reads 5 blocks on the disk. While the system is idle it has nothing else to do so your 5 blocks are read immediately, super fast.

While the system is doing some other I/O intensive job, it might be doing 500 block reads at the same time. Everything goes in the same queue, so your task is only %1 of the requests that have to be done in a set time. Result: Your task takes 100 times longer.

This is the problem that all the scheduler are trying to solve: trying to be fair so that every task gets a reasonable share of priority, while keeping performance at an optimum level.

For example, some O/S researchers have tried to implemented multiple-tiered system where every I/O is tagged with flags that indicate if the call came from an interactive user action, or was generated by non-interactive jobs (daemons, lower-level layers, etc...) and then give higher priority to the user requests. Two problems with that approach is it can be very hard to differentiate the two and that any heavy user task may prevent system tasks to work in a timely fashion and the user tasks may depend on the system tasks to complete their jobs in order to proceed; vicious circles and race conditions.

I'm glad I'm not trying to code a kernel scheduler, they're very hard problems and figuring one out that can be fair for all types of uses is nigh impossible.

The great thing about the open source O/Ss is that everything's done in the open, there's intense discussions going on about in the field, and there's multiple solutions being worked on and tested.

To me, Linux has always felt like it gave much higher priority to I/O than the "user experience". It's something I've come to expect. If I copy gigabytes from a disk set to another I gladly accept that my web browser's going to be sluggish for a time, all the while feeling content that at least it's going to be done so efficiently that it's going to last for the shortest amount of time possible.

Other O/Ss that I won't name may "feel" better, but have nowhere near the same I/O throughput that Linux has.

Comment Re:What about logging in over public WiFi? (Score 1) 427

Sharing a password with your wife, assuming you trust her, not that big of a deal.

It's a big deal and not a good idea. When your security is broken for whatever reason (trojan, key logger, intrusion, etc...) you don't want to have the extra trouble that a tiny possibility of a doubt exists that maybe, just maybe, your wife did it.

Comment x264 WebP JPG (Score 1) 378

The guy at the englishhard.com makes a strong argument for x264 with a proper comparison with non-compressed images upfront. Google has a bad history of not being able to admit they're not the best at everything, and in this case, for my money, they sure aren't.

Submission + - Today Google has learned not to change their .... (wsj.com)

An anonymous reader writes: Some time ago, Coca-Cola learned that they should not change the flavour of Coke. Today Google has learned that the simplicity of their homepage (including the white background) is something that Google Users value the most. Branding is essential, and definetely trying to look like Bing is not a good thing for Google.

Comment Re:More than 10 years ago? (Score 1) 505

Didn't know of any 486 machines that supported booting from any zip drive, much less a parallel one. I call bullshit.

The only 486 I can find right now reports:

# dmidecode |grep Zip
                                ATAPI Zip drive boot is supported
#

I remember a 486/66 waaaaay back when that also supported parallel Zip and booting from it in the BIOS options. Wasn't bad for DOS but booting Linux took forever.

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