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age 35
visits member for 2 years, 11 months
seen 3 hours ago

Apr
10
awarded  Notable Question
Apr
9
answered Why do I have to cd out of a deleted directory?
Apr
9
comment File has bytes - appears to be empty
Then there you go; it crashed and rebooted before the data hit the disk, so it was lost.
Apr
9
comment How to get CPU Percentage as a Counter?
@KyleBrandt, either you want the percentage of utilization, in which case, you have to divide by uptime, or you want a count of non idle time, which is not a percentage.
Apr
9
comment How to get CPU Percentage as a Counter?
@KyleBrandt, no, it does not "work out", which is why you are getting all sorts of goofy numbers. You have to have a divide by uptime in there, like goldilocks's answer shows.
Apr
9
comment How to get CPU Percentage as a Counter?
@KyleBrandt, no, measuring something in centisecs does not make it a percentage. Calculating the ratio of that measurement to a theoretical maximum does.
Apr
9
comment Why is writing so slow on raw device, and so fast on filesystem (USB key)?
@Bananguin, no, it gets better when you write to a different part of the disk. The fact that the filesystem happened to cause that is incidental. Depending on what filesystem you used what else is on the disk, it very well may have decided to put the file in the "slow" part of the disk instead.
Apr
9
comment Why is writing so slow on raw device, and so fast on filesystem (USB key)?
@mikeserv, see ccs.neu.edu/home/pjd/papers/fast10-flash.pdf, and idke.ruc.edu.cn/people/dazhou/Papers/AsurveyFlash-JSA.pdf
Apr
8
answered Why is writing so slow on raw device, and so fast on filesystem (USB key)?
Apr
8
comment Shrink/reduce non-lvm disk file system
If there is no partition then there should be no 1 following /dev/sdd.
Apr
8
comment File has bytes - appears to be empty
Did you neglect to mention that your system crashed/lost power shortly after you wrote that file?
Apr
8
comment Why is writing so slow on raw device, and so fast on filesystem (USB key)?
@Bananguin, the "optimization" is to avoid fragmenting files, keeping the IO contiguous. dd to the raw block device is all contiguous, so that is as good as it gets.
Apr
8
comment Why is writing so slow on raw device, and so fast on filesystem (USB key)?
@mikeserv, the block device interface caches direct access to block devices.
Apr
8
comment Why is writing so slow on raw device, and so fast on filesystem (USB key)?
The filesystem will be writing the file somewhere other than the start of the partition. Perhaps there is something wrong with the area near the start? Try a single dd but with higher seek arguments to write to different parts of the disk.
Apr
8
comment Why is writing so slow on raw device, and so fast on filesystem (USB key)?
Writing directly to a block device does use the cache.
Apr
7
answered Can swap be shared safely while hibernating?
Apr
7
comment While trying to open /dev/mtd2 for read/write access: Permission denied
@Graeme, giving everyone read permission to a block device isn't a good idea, and isn't going to help with write access.
Apr
3
comment Ext2 block structure: size of reserved GDT Blocks
@goose999, I checked the source and it seems that the number of reserved blocks is capped at how many will fit in a single indirect block, which for 1k block size is 256. I guess they didn't want to be bothered with having to allocate more than a single indirect block.
Apr
2
comment Ext2 block structure: size of reserved GDT Blocks
@goose999, ahh, I forgot about that silly arbitrary limitation on the smaller block sizes. In that case, it should be 13 ( you can only have a whole number of block groups ) * 32 = 416 blocks.
Apr
2
comment Ext2 block structure: size of reserved GDT Blocks
@goose999, you should only have 4 block groups, so 4 * 32 = 128 bytes, so 1024 times that is 128 blocks.