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Comment Re:article is BS (Score 1) 430

Influenza causes only a small minority of all deaths in the U.S., even among senior citizens,

36,000 die of complications from the flu annually in the US. That's very nearly as many as die from car accidents.

It is entirely accurate to say flu deaths are a minority of all deaths. According to the CDC in 2006 there were 56,326 deaths from Influenza and Pneumonia, out of a total of 2,426,264 deaths. If we assume all of those 56,326 deaths were from the flu, that is a grand total of 2.3% of all deaths from the flu. If the number is actually 36,000 (which sounds reasonable once you factor out Pneumonia) then it is only ~1.5%.

Of course that has nothing to do with the accuracy of the story, but lets not jump on the parts where we actually have reasonable data.

Comment Re:Erlang Anyone? Anyone? (Score 1) 342

Erlang is very cool, but it is not designed to replace C. In fact, it is designed to handle some bits of the higher level concurrency stuff and call out to C "drivers" for level work. Apparently Ericsson's switch code has almost as much C/C++ code as Erlang code. GCD addresses concurrency in problem spaces Erlang is completely inappropriate for, just like Erlang plays in spaces that GCD is not appropriate for. They are different tools for different jobs.

Comment Re:Wrong data in article? (Score 3, Informative) 156

No, what the actual situation is is that a block consists of some number of pages (currently on the flash used in SSDs it tends to be 128). The pages can be written individually, but only sequentially (so, write page 1, then page 2, then page 3), and the pages cannot be erased individually, you need to erase the whole block.

The consequence of this is that when the FS says "Write this data to LBA 1000" the SSD cannot overwrite the existing page it is stored without erasing its block, so instead it find somewhere else to store it, and in its internal tables it marks the old page as invalid. Later when the GC is sweeping blocks for consolidation the number of valid pages is one of the criteria it uses to figure out what to do. If a block has very few valid pages and has been completely filled then those pages will probably be copied to another block that is mostly valid and the block the data was originally in will be erased.

Comment Re:Filesystem info (Score 5, Informative) 156

There is an extensions that was recently added to ATA, the TRIM command. The TRIM command allows an OS to specify a blocks data is no longer useful and the drive should dispose of it. No productions support it, but several beta firmwares do. There are also patches for the Linux kernel that adds support to the black layer along with appropriate support to most filesystems. Windows 7 also has support for it.

There is a lot of confusion about this on the OCZ boards, with people thinking GC somehow magically obviates the needs for TRIM. As you pointed out the GC doesn't know what is data and what is not with respect to deleted files in the FS. I wrote a blog post (with pictures and everything) explaining this just a few days ago

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