Which disk access is faster?faster

[fretful]

Hi,

Which of the following two scenarios is faster, given that all other factors would be the same:

One disk accessed twiced, once at each edge (inner and outer) OR

Two disks simultaneously accessed once each.

The reason for this query is I want to know if it will speed-up my PC if the OS is on one drive and the applications are on another?

Regards,

Fretful.

[Vulcan]

Which of the following two scenarios is faster, given that all other factors would be the same:

There are other factors which you haven't mentioned (doesn't matter if they're the same or not, between the 2 configs) which will affect whether or not you actually measure much performance difference, but...

One disk accessed twiced, once at each edge (inner and outer) OR

Two disks simultaneously accessed once each.

From all my experience on performance investigations, I have never seen two I/Os to one disk (especially with a seek between them), be faster than one I/O to each of two disks (since these could be done in parallel) - i.e. the latter is typically faster. However, there are other factors about the exact usage, which might make the performance difference minimal.

The reason for this query is I want to know if it will speed-up my PC if the OS is on one drive and the applications are on another?

Although using 2 disks, as you describe above, has the potential for some PC operations to be faster, I could construct some tests which would show minimal useful improvement and other tests which would show significant improvement. In other words - YMMV.

Since this forum isn't dedicated to PC performance & configuration, then this may not be the best place for you to ask your question. However I/O performance (on *nix-based systems) is something I've worked on for many years, so with the limited info available, I've given you some general info to answer your question.