sg_sync - send the scsi command synchronize cache

sg_sync [--count=<n>] [--group=<n>] [--help] [--immed] [--lba=<n>] [--sync-nv] [--verbose] [--version] <scsi_device>

Send SYNCHRONIZE CACHE (10) command to a Linux SCSI device. This command is defined for SCSI block devices (see SBC-2). If successful this command makes sure that any blocks whose latest versions are held in (volatile) cache are written to (also termed as "synchronized with") the medium. If the '--sync-nv' option is given and the device has a non-volatile cache then any blocks whose latest versions are held in volatile cache are written to non-volatile cache.

If the arguments to '--lba' and '--count' are both zero (their defaults) then all blocks in the cache are synchronized. If '--lba' is greater than zero while '--count' is zero then blocks in the cache whose address is from and including the '--lba' argument to the highest lba on the device are synchronized. If both '--lba' and '--count' are non zero then blocks in the cache whose addresses lie in the range lba_argument to lba_argument+count_argument-1 inclusive are synchronized with the medium.

--count=<n> | -c <n>

number of block to synchronize from and including the '--lba' argument. Default value is 0. When 0 then all blocks in the (volatile) cache from and including the '--lba' argument to the highest block address are synchronized.

--group=<n> | -g <n>

the group number can be between 0 and 31 inclusive. The default value is 0 . Group numbers are used to segregate data collected within the device. This is a new feature in SBC-2 and can probably be ignored for the time being.

--help | -h

output the usage message then exit.

--imm | -i

sets the "imm" bit in the SYNCHRONIZE CACHE command. This instructs the device, if the format of the command is acceptable, to return a GOOD status immediately rather than wait for the blocks in the (volatile) cache to be synchronized with (i.e. written to) the medium (or the non-volatile cache).

--lba=<n> | -l <n>

the lowest logical block address in the (volatile) cache to synchronize to the medium (or the non-volatile cache). Default value is 0 .

--sync-nv | -s

synchronize the (volatile) cache with the non-volatile cache. Without this option (or if there is no non-volatile cache in the device) the synchronization is with the medium.

--verbose | -v

increase the level of verbosity, (i.e. debug output).

--version | -V

print the version string and then exit.

The arguments to --count, --group and --lba may be followed by one of these multiplicative suffixes: c C *1; w W *2; b B *512; k K KiB *1,024; KB *1,000; m M MiB *1,048,576; MB *1,000,000 . This pattern continues for "G", "T" and "P". Also a suffix of the form "x<n>" multiplies the leading number by <n>. The "T" and "P" suffixes can only be used for --count and --lba.

Alternatively numerical values can be given in hexadecimal preceded by either "0x" or "0X". When hex numbers are given multipliers cannot be used.

Written by Douglas Gilbert.

Report bugs to <dgilbert at interlog dot com>.

Copyright © 2004-2005 Douglas Gilbert

This software is distributed under a FreeBSD license. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

sg_start(sg3_utils)