Admittedly, I am running on a build that is no younger than five years old at this point and the system is not going to be incredibly fast. However, at the same time, the run-times I am observing are so painfully slow it's urged me to create this question to see if there was something I could do to fix this problem.
For example, I was simply unpacking a tarball, albeit quite a large one (~15GB), and the entire process took about 2.5 hours with about 9 minutes of actual CPU time. In contrast, the creation of this tarball took about just a few minutes. Again, the creation was on a fairly adept machine, but 2.5 hours seems far too slow.
As a second example, building a particular project (on the adept machine) took only 19 seconds, with 17 of those seconds being actual CPU time. In contrast, the same process took nearly 9 minutes (on this slower machine) with only about 14 seconds being actual CPU time. As you can see below, the actual CPU time is fairly similar, it's just the total execution time that is the problem.
Adept Machine
real 0m19.245s
user 0m15.809s
sys 0m0.908s
Current Machine
real 8m37.500s
user 0m11.175s
sys 0m3.969s
I include the unfair comparison between the two machines only as a reference point. There is nothing particularly amazing about the adept machine, it's just quite a bit newer.
Ubuntu in general tends to be quite a bit more sluggish than it should be, often times freezing for a few moments before resuming. Opening tasks tends to take a lot of time as well - as much as 20-30 seconds for something as simple as Eclipse; browsers can take 5-10 seconds as well.
- Ubuntu 14.04 -- Full-disk encryption enabled
- Core i-7 860 @ 2.8Ghz
- WD2500JS 7200RPM SATA 3Gbps 8MB Cache
tldr; Why is there such a huge gap between total execution time and actual CPU time? The disk I am using is not that slow. It's hard to believe the disk being the source of such a huge discrepancy. Perhaps it's the first-gen i7?
