Get the correct size for block devices #207
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The function `Size()` of `FileInfo` returns the length in bytes for regular files. However if we use a block device, `Size()` will return a length of zero. To chunk a file, we use the size to split the expected work in even parts. For this reason, when we wanted to generate an index from a block device, due to the incorrect reported zero size, the whole task was carried out by a single Goroutine. With this commit we use the ioctl `BLKGETSIZE64` to get the correct size for block devices. In a test environment the `make` operation against a block device took 2 minutes and 20 seconds to complete with the current master branch and only 24 seconds with this patch. Signed-off-by: Ludovico de Nittis <ludovico.denittis@collabora.com>
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The function
Size()ofFileInforeturns the length in bytes forregular files. However if we use a block device,
Size()will return alength of zero.
To chunk a file, we use the size to split the expected work in even
parts.
For this reason, when we wanted to generate an index from a block
device, due to the incorrect reported zero size, the whole task was
carried out by a single Goroutine.
With this commit we use the ioctl
BLKGETSIZE64to get the correct sizefor block devices.
In a test environment the
makeoperation against a block device took 2minutes and 20 seconds to complete with the current master branch and
only 24 seconds with this patch.