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Utorrent has inspired me


Pwnage

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FASTIO_READ are a lot less expensive on the system than normal reads, so it doesn't really matter how many reads they make. They're reading from the cache.

That makes no sense, how is it less taxing of the system when it reads more and more, even if it reads from cache its still overreading. 1 million reads in alittle over an hour is excessive, dont you think?

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I don't believe a hard disk's failure rate is measured in just reads/writes, but rather how long it has stayed online (MTBF - Mean Time Between Failure). Most hard disks have a MTBF of what, 100,000 hours? The Raptors have something like 1.2 million hours...so if you need reliability, that's where I'd put my money on. I'm excluding SCSI drives as not all of us can afford such gems... ;)

Edit: typo...sigh... :/

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Pwnage: http://web.archive.org/web/20031005043605/http://www.osr.com/ntinsider/1996/fastio.htm

This tight integration means that both read and write operations can often be satisfied from this cached data. In the search for performance, then, this fact can be exploited for read and write by simply calling a specialized routine which moves data from the VM cache into the user's memory, or vice versa. This eliminates the need to allocate an I/O request packet since the operation can be satisfied synchronously and need not call into lower drivers. It is this fundamental model which is realized by the fast I/O operations.
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It doesn't matter. Cache reads don't matter.

Winamp, on the other hand, performs a ton of non-cache reads (IRP_MJ_READ) and directory opens/closes, which is far, far worse than foobar2000. Unlike foobar2000's cache reads, these slow reads DO have an impact on the system.

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It doesn't matter. Cache reads don't matter.

Winamp, on the other hand, performs a ton of non-cache reads (IRP_MJ_READ) and directory opens/closes, which is far, far worse than foobar2000. Unlike foobar2000's cache reads, these slow reads DO have an impact on the system.

Other than you ive never heard anyone say that its far far worse... Wheres your proof for that, or are you just making stuff up, im just glad I didnt spend hours and hours trying to get my music player to look like a music player.

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FASTIO_READ is from the system cache. IRP_MJ_READ is not, and is a fairly slow (relatively speaking) read from the disk. Winamp makes lots of those. About half the reads, actually. It also queries the plugins directory every second, making 4 IO calls every second.

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If Winamp really reads the file using IRP calls as often as foobar2000 reads from cache using FASTIO, then yes, it's probably more harmful than foobar2000 (and marginally at that), though I can't really prove that claim, since I'm not sure how damaging and expensive the calls really are to the hard drive either. Just a guess based on what I'm understanding so far.

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