i7 Quad core hyper threaded = 4 threads?

[thx1128]

When I batch transcode lossless files I seem to be limited to 4 threads although the CPU I use (i7 family) is capable of 8 threads. Is this a limitation of the software or is there a setting that I missed?

[Spoon]

Re: i7 Quad core hyper threaded = 4 threads?

4 is currently the limit of the software, that said Hyper Threading is a bit of a marketing thing if you ask me.

[Michael Sargent]

Re: i7 Quad core hyper threaded = 4 threads?

Hyper Threading is a bit of a marketing thing if you ask me.

Hyperthreading does help in some cases, but with batch music conversion I find that 4 threads is way more than enough to run out of I/O bandwidth (disk) long before the CPUs are fully used.

I have converted DVD Audio (MLP 96/24/5.1 ripped as Wave to WMA Lossless) from SSD to USB 2.0 drive and that runs out of USB bandwidth with the CPUs at around 30%. I did try some SSD to SSD conversions and that would run the CPUs up to only about 85%. I don't think more threads would speed anything up there.

Once we are all running SSDs on SATA 6GB (or USB 3.0), there might be some justification for trying to use Hyperthreading, but for the time being i7's are way faster than disk.

Mike

[Shin0bi272]

Re: i7 Quad core hyper threaded = 4 threads?

I'd rather the program at least start 8 threads even if it doesnt have enough disk bandwidth to write immediately. By not employing this you will be stifling people who have ssd's or raid setups. It's also a nice benchmark for testing your system. 4cores with ht vs 4 cores converting 10 songs which one finishes faster? see you have a benchmark to test systems

[edit] Im currently converting about 10k files on 2 pc's. my i7 is going over the network (1gb/s) to my sata 150 drive in my old p4 3ghz northwood where that cpu is hard at work converting 676 of that 10k. According to resource monitor my hard drive is reading in 1.7mB/sec and writing 1.7mB/sec which is no where near the max bandwidth of the drive. The cpu is maxed on the northwood of course (making this post difficult lol) but the i7 is snappy and responsive with 1 core still sitting idle. So I think its safe to say that enabling HT on dbpoweramp for i7's will be fine [/edit]

[smoorenc]

Re: i7 Quad core hyper threaded = 4 threads?

I am running with (2) Xeon Quad cores and it still only shows 4. I would love to beable to have it use all 8. On my CPU usage meter it shows all 8. When I start up a conversion I can see the 4 it is using. Cool! But I would still like to have all 8 usable for conversions.

[eeeeh]

Re: i7 Quad core hyper threaded = 4 threads?

4 is currently the limit of the software, that said Hyper Threading is a bit of a marketing thing if you ask me.

Whaaat?
Hyper-Threading gives 50% performance boost in unbiased 3D rendering.

Anyway, with HT on I get 65x encoding speed.
Without it 85x.

So supporting 8 threads would probably boost performance, as the CPU obviously isn't utilized to the fullest with HT on.

[Spoon]

Re: i7 Quad core hyper threaded = 4 threads?

That precisely shows it can slow down conversion, or put another way if you had a CPU with 32 cores it should not be slower than one with 4 cores, even if only 4 cores are being used, it should be the same speed!

[eeeeh]

Re: i7 Quad core hyper threaded = 4 threads?

Yeah it gives worse performance with it enabled, but even though it's using 100% CPU, it isn't utilizing 8 threads.

With indigo renderer, when disabling HT, I get 50% worse performance, but it's still using 100% CPU at 4 threads. The renderer supports 8 threads.

So will it have no effect to support hyper threading in software?

According to Intel themselves: ...and improved performance on the multi-threaded software of today and tomorrow.

[Robmoo]

Re: i7 Quad core hyper threaded = 4 threads?

I use DB power Amp to convert audio book files to m4b files and lower bit rate mp3 files. With my Ci7 920 DBPowerAMP is using less than 50% of my processing power. I wish it supported up to 8 threads so I could cut the time in half. I have a pair of SSD's so my HD read/write speeds are around 500mbps so they should be fast enough to support the faster conversion speed.

The hardware is getting faster. The software has to keep up. I'm willing to pay for the upgrade.

[Spoon]

Re: i7 Quad core hyper threaded = 4 threads?

See R14 i nthe beta section of this forum, it supports 16 cores.