> I just rebuilt my dev machine and I'm using one SSD drive for the OS, one SDD for data (database, Cassandra stuff), and then a regular drive to hold code and builds ...
So instead of one large storage pool, you have three. This means your chance to have your system grind to a halt with a disk-full condition is three times greater than it would otherwise be.
I've never understood this logic, but I certainly see it implemented a lot. It's a new version of disk hard-partitioning in *nix systems -- a scheme that stopped making sense once drives because large enough to contain all the resources on one unit.
With one drive containing all stored resources and no hard partitions, there's exactly one disk-full failure mode -- when the disk is full.
When Charles Lindbergh was asked why he wanted only one engine on his historic Atlantic-crossing plane, he replied that, since the multi-engine planes of his day couldn't stay airborne on one engine, his design was actually safer.
I used to have the same opinion you did until I started doing some really filesystem intense stuff (not even big, just lots of creating and deleting of files) and suddenly my entire system ground to a halt. Huge delays (top showed state "D"—waiting for device).
I moved that stuff to its own disk and my system became smooth as butter again.
I'm still not down with the traditional unix '"/usr" must be its own partition!' thing, but it does help to separate your tasks onto separate disks.
If he combined them, it would be likely he would have to move to an HDD to fit everything. The part that's really unfortuante about that is that HDDs do not have the best reading/writing since the heads actually need to seek the data. These creates performance bottlenecks, especially if he's trying to transfer a build while the database is active.
Fewer disks, less chance of failure. it's extra important to back up though, since one disk failure can result in entire catastrophe! Losing an OS but still having DB and Code isn't that catastrophic.
So instead of one large storage pool, you have three. This means your chance to have your system grind to a halt with a disk-full condition is three times greater than it would otherwise be.
I've never understood this logic, but I certainly see it implemented a lot. It's a new version of disk hard-partitioning in *nix systems -- a scheme that stopped making sense once drives because large enough to contain all the resources on one unit.
With one drive containing all stored resources and no hard partitions, there's exactly one disk-full failure mode -- when the disk is full.
When Charles Lindbergh was asked why he wanted only one engine on his historic Atlantic-crossing plane, he replied that, since the multi-engine planes of his day couldn't stay airborne on one engine, his design was actually safer.