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I've recently upgraded my desktop after eight years. Moving from an i7-2600K/16GB RAM/SSD & spinning disk/GTX970 to a Ryzen 3950x/64GB RAM/PCIe4 NVME/2080 Super. (Hoping to get another long-lasting machine.) To get an idea of the performance differential, I ran the "timtaw screening-long" suite of tests (https://openbenchmarking.org/suite/t...screening-long) on the old machine before I sent it off to a loving home:
I don't remember exactly how long it took to run (and I can't find the number on that page; is there a way to check?) but I'm sure it took less than 24 hours. However, I kicked off the same suite on the new box (running "phoronix-test-suite benchmark 2001299-HU-OLDBOXBAS88") at just after 11pm on Sunday Feb 23. It's now over 30 hours later and the tests are still running. (It's made it to pgbench v10.3 "Scaling: On-Disk - Test: Heavy Contention - Mode: Read Write". Still a ways to go...)
Now, the raw numbers on the new machine are, of course, significantly better than the old ones. The test just before it, "Scaling: On-Disk - Test: Heavy Contention - Mode: Read Only" went from ~18K tps to ~100K tps. But the runtime is nothing like the estimate of "38 minutes" to run. Each individual test run (of three) is over an hour.
In general, I'd expect benchmarks to either run faster on a more powerful machine (same amount of work, done faster) or at least the same time (more work done in X amount of time). Is there something about pgbench that makes it run longer when given more resources? At the current rate, I'm not likely to be able to use my new machine for another twelve hours or so...
I don't remember exactly how long it took to run (and I can't find the number on that page; is there a way to check?) but I'm sure it took less than 24 hours. However, I kicked off the same suite on the new box (running "phoronix-test-suite benchmark 2001299-HU-OLDBOXBAS88") at just after 11pm on Sunday Feb 23. It's now over 30 hours later and the tests are still running. (It's made it to pgbench v10.3 "Scaling: On-Disk - Test: Heavy Contention - Mode: Read Write". Still a ways to go...)
Now, the raw numbers on the new machine are, of course, significantly better than the old ones. The test just before it, "Scaling: On-Disk - Test: Heavy Contention - Mode: Read Only" went from ~18K tps to ~100K tps. But the runtime is nothing like the estimate of "38 minutes" to run. Each individual test run (of three) is over an hour.
In general, I'd expect benchmarks to either run faster on a more powerful machine (same amount of work, done faster) or at least the same time (more work done in X amount of time). Is there something about pgbench that makes it run longer when given more resources? At the current rate, I'm not likely to be able to use my new machine for another twelve hours or so...
But Pgbench is designed to scale to hundreds of CPU cores and hundreds of GB of RAM.
In the meantime I'll chalk this one up to experience and use it as an opportunity to exercise patience.
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