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Intel Confirms It Will Ship 160GB Flash Drives
Lucas123 writes "Intel has confirmed plans to ship a new line of solid-state drives for laptop and notebook PCs with storage capacities of 80GB to 160GB. While it did not lock in a ship date, Intel told Computerworld that the drives would be available in the second quarter. From the story: 'An aggressive move into the laptop and PC notebook flash disk drive business would catapult Intel into direct competition with hard drive manufacturers such as Toshiba Corp. and Samsung Electronics Co. that are trying to spark demand before their SATA-based offerings are released in the coming months.'"
160 = 10 x 2^4. So, probably 10 x 16GB chips
I'm curious at what point we will quit treating these hard drive replacements as that, and instead treat them as what they are - large arrays of addressable memory. Without doing the homework to be sure, I suspect that being able to remove the overhead of an OS building the needed protocol stream to address this memory as a hard drive, and instead treating it as memory, would save significant(?) code/time.
Current hardware with simple wear leveling will give you about a solid year of continuous writes. That's writing 24/7, nonstop. I don't think a HDD could even survive that. For a consumer device, even under fairly heavy use, the hardware will be long obsolete before it runs out of write cycles.
Done with slashdot, done with nerds, getting a life.
Hmm...
I just found this:
Unlike DRAM, flash memory chips have a limited lifespan. Further, different flash chips have a different number of write cycles before errors start to occur. Flash chips with 300,000 write cycles are common, and currently the best flash chips are rated at 1,000,000 write cycles per block (with 8,000 blocks per chip). Now, just because a flash chip has a given write cycle rating, it doesn't mean that the chip will self-destruct as soon as that threshold is reached. It means that a flash chip with a 1 million Erase/Write endurance threshold limit will have only 0.02 percent of the sample population turn into a bad block when the write threshold is reached for that block. The better flash SSD manufacturers have two ways to increase the longevity of the drives: First, a "balancing" algorithm is used. This monitors how many times each disk block has been written. This will greatly extend the life of the drive. The better manufacturers have "wear-leveling" algorithms that balance the data intelligently, avoiding both exacerbating the wearing of the blocks and "thrashing" of the disk: When a given block has been written above a certain percentage threshold, the SSD will (in the background, avoiding performance decreases) swap the data in that block with the data in a block that has exhibited a "read-only-like" characteristic. Second, should bad blocks occur, they are mapped out as they would be on a rotating disk. With usage patterns of writing gigabytes per day, each flash-based SSD should last hundreds of years, depending on capacity. If it has a DRAM cache, it'll last even longer.
You forgot the 10x increased chance of unrecoverable failure.
The ONLY way you can defragment a file is to copy the fragmented file to another partition, remove it and copy it back. If you want to defragment a complete ext2/3 filesystem, make a backup of the filesystem using tar, delete the original and restore the backup.
No, this is not something you want to do while other software may be looking for the file.
Of the common filesystems available for Linux (ext2/3, xfs, jfs, reiserfs) the only one that supports online defragmentation is xfs (using the xfs_fsr utility) and this has to be scheduled manually.
Fragmentation in ext2/3 files is a huge problem when appending to files over long periods of time. You can check the fragmentation of any file on ext2/3 using the filefrag utility. Make a copy of a highly fragmented file (even to the same partition) and you will see the number of fragments go down dramatically, unless you don't have much free space left on the partition and the space you have free is also highly fragmented.
However, your defrag method IS NOT SAFE and WILL RESULT IN DATA LOSS on a live system (sorry to yell, but I don't want anyone trying it on a live system - it should be OK if you can guarantee that no-one else will modify the data on the partition)
There is a lot of opportunity in your script for data loss:
1. During the copy. If someone modifies part of the original that has already been copied, your
2. During the rm. Deleting files takes time, so there is more room for a file to try to write to the original. This step is actually completely unnecessary, just overwrite the original with your mv command.
3. After the mv. If a process has the original file open, it will continue writing to that original file, even after it's been deleted and "overwritten". It is very legal to continue file operations on an open file descriptor.
I suggest you actually try your defragmentation trick on a live filesystem which is actively in use. If you don't lose data, you're lucky.
So I'll say it again. The only filesystem which allows you do perform LIVE defragmentation is xfs using it's xfs_fsr utility.
As far as random access on a drive is concerned, a 5MB music file is gigantic. The seek time (1 seek every 3-4 minutes) is a non-issue. If you were playing 20 snippits of different songs every second then it might matter, but for MP3 playing it is not an issue at all. Even if your file gets fragmented for some reason you're only going to be talking about a few dozen seeks at most.
That said, flash does have a bunch of advantages for music players. It's far more shock resistant (for running!), requires less power, and doesn't have to constantly be put to sleep and woken up like spinning magnetic media.
I read the internet for the articles.