ramdisks [a solution]
Mike Wright
mike.wright at mailinator.com
Thu Apr 16 18:25:47 UTC 2009
Bill Davidsen wrote:
> Mike Wright wrote:
>> I came up with a solution that uses LVM and it works a *charm*,
>> albeit, probably because of large block sizes relative to the 16M size
>> of the ramdisks, seems inefficient (costs 25% each). Maybe I can tune
>> these and get better.
>>
>> pvcreate /dev/ram15
>> pvcreate /dev/ram14
>> pvcreate /dev/ram13
>> pvcreate /dev/ram12
>>
>> vgcreate my36Mdisk /dev/ram15 /dev/ram14 /dev/ram13
>> vgcreate my12Mdisk /dev/ram/12
>>
>> lvcreate -n myRamDisk1 -L 36M my36Mdisk
>> lvcreate -n myRamDisk2 -L 12M my12Mdisk
>>
> Wow that sounds complex, why not just make the ramdisks larger? Just use
> the boot parameter which sets that:
> ramdisk_size=N
> where N is the size in kilobytes, so for 256M you specify 262144.
>
Thanks for that advice.
I ended up making the ramdisks smaller which gave me greater
granularity. Then when the volume groups were created I specified 64K
extents instead of the default 16M. That gave two benefits: there was
almost no wasted space in the VG, and the data that I copied over used
less than half of the space of the original.
:m)
More information about the fedora-list
mailing list