To Hyper Thread or not.....

Intel currently has the market lead in CPU technology with its 2nd gen Sandy Bridge processors.

There are two that get a lot of mention with regards to photo editing, the i5 2500 and the i7 2600.

Both are Quad Core, both have Turbo Boost, and while the i7 2600 is a few mhz faster, it's biggest difference is it's ability to Hyper Thread (i.e. create virtual cores).

There was some debate recently about whether or not Hyper Threading was actually of any use when photo editing. I.e. If an i7 2600 was worth the extra $100 over the i5 2500.

So, as I own an i7 2600k, I ran some simple tests.

I shoot with a 5D Mark II, so have no problem generating large files that make very good use of the i7 2600K's performance, I have seen all 4 real, and 4 virtual cores used when working.

I ran 3 tests, each with Hyper threading enabled, and disabled.
All tests were done using LR3 which uses as many cores as it has access to, and I have found to be a very, very heavy CPU user.

Test 1:
Export 193 5D2 RAW files to 800x800px JPEG's, reading and writing to separate drives.

Test 2:
Export 5 5D2 RAW files to 800x800px JPEG's, reading and writing to separate drives, while playing MineCraft

Test 3:
Use the LR3 Adjustment brush to draw all over a RAW file with a big exposure and saturation adjustment.


The Results:

For Test 1 and Test 2, there was no meaningful difference at all in the time it took.
I have a suspicion that the process may have been disc limited though as the cores didn't reach 100%, with or with out hyper threading.

I think it needs to be run with an SSD to really test it.


Test 3 however was the most interesting.

I used to have Q6600 Core 2 Quad, which in it's day was a fantastic CPU.
But the 5D2's large files showed the Q6600 limitations most when using the LR 3 adjustment bush.
It used to tun all 4 cores to 100% and the brush would lag, a lot.
It lagged so much that making large adjustments was impossible as they could take several seconds to render on the screen.

Using the LR3 Adjustment Brush on the i7 2600K however is a completely different story. It's smooth and responsive, just like using a brush in Photoshop. That is with Hyper Threading Enabled.

With Hyper Threading enabled the brush works perfectly, no matter how big an area, or how big an adjustment I try to make.
It is interesting to note that all 4 real and 4 virtual cores are run at about 25%.

With Hyper Threading dis-abled all 4 cores ran at closer to 75% each AND there was a noticeable Lag in the brush, up to a second or more when covering large areas at once.
It made the brush hard to use, especially for any attempt at detail work.
While better than the Q6600, I would have been disappointed with it as an upgrade.

So, does this mean the i7 2600 is worth the extra dollars?
If all your doing is basic conversions and exporting RAW to JPEG, then no it's not.

But, if your doing more, or looking for something that is more likely to more future proof, then the i7 2600 is worth it.
It's very clear that LR3 can and does make use of all the Cores, the huge difference when using the Adjustment Brush is proof enough of that.
Given how much I use the Adjustment Brush, I'm very glad I got the i7 rather than the i5.

I really have a huge dislike for intel right now. I don't understand why they chose to remove hyper threading from their current generation i3 and i5 line when the previous generation had the technology.

My dual core i3 has hyper threading, but the brand new quad core i5 does not. This kind of feature disparity is misleading...and ridiculous.

I don't understand how hyper threading swaps between a premium feature and a standard feature every few years.

Nice review, though I am afraid that for most users, intel has thrown us under a bus. Jerks.

sbattey wrote in post #13145096
I really have a huge dislike for intel right now. I don't understand why they chose to remove hyper threading from their current generation i3 and i5 line when the previous generation had the technology.

My dual core i3 has hyper threading, but the brand new quad core i5 does not. This kind of feature disparity is misleading...and ridiculous.

I don't understand how hyper threading swaps between a premium feature and a standard feature every few years.

Nice review, though I am afraid that for most users, intel has thrown us under a bus. Jerks.

Quad-core i5s have never, as far as I know, had HyperThreading. However in this generation, and the previous ones, the dual-core chips are HyperThreaded.

Marcus X wrote in post #13145951
Quad-core i5s have never, as far as I know, had HyperThreading. However in this generation, and the previous ones, the dual-core chips are HyperThreaded.

Yip, only the Quad i5 don't have Hyper Threading.
The Dual Core i5 and i3 chips do.
The i3 don't have Turbo Boost, but the Dual Core and Quad Core i5's Do.

Then the i7's have everything, Quad Core, Hyper Threading and Turbo Boost.
Except for some of the mobile versions, that are only Dual Core.

Moppie, can you try doing an LR export at the same time as running the image processor script in photoshop to save convert full res jpegs down to 600px web size jpegs? That will give an idea about multitasking ability. Another possible test is running multiple exports in LR instead of just one, I hear that increases CPU use and throughput significantly.

tim wrote in post #13148236
Moppie, can you try doing an LR export at the same time as running the image processor script in photoshop to save convert full res jpegs down to 600px web size jpegs? That will give an idea about multitasking ability. Another possible test is running multiple exports in LR instead of just one, I hear that increases CPU use and throughput significantly.

Doing two exports will just put more load on the HDD, which I think is already unable to keep up.
There is a noticeable drop in CPU performance as each file is loaded for conversion.
It really needs to be done reading from and writing too and SSD (or pair of SSD's)

I can run it with the re-size at the same time though, as they does not have to save to disc, and it can do it from images stored in memory.

The problem is timing it in such away that both processes start at the same time.

If you run two exports at the same time maybe it be processing one file while it loads the other from disk. It's worth a shot anyway.

On my old PC it's the CPU that can't keep up, so knowing it's disk means performance will be a lot higher anyway.

SSDs throughput isn't always better than hard drives, unless you have really new SSDs. My SSDS are SATA3, haven't performance tested them but from memory throughput is similar to a big new drive. It's really only latency that SSDs win at. New SSDs are getting faster though, they spread the data across more disks so it can get more back at a time.

Marcus X wrote in post #13145951
Quad-core i5s have never, as far as I know, had HyperThreading. However in this generation, and the previous ones, the dual-core chips are HyperThreaded.

Thanks for the clarification. But still, you can't argue that these feature disparities aren't stupid.

Ars Technica did an article on this (I think it was ars) detailing feature disparities between their lines of processors.

It almost reminds my of the fail that microsoft released with Vista, having all of the different versions have different features, with no clear reasoning behind left off features and ones that were included between versions.

sbattey wrote in post #13149197
It almost reminds my of the fail that microsoft released with Vista, having all of the different versions have different features, with no clear reasoning behind left off features and ones that were included between versions.

It's what happens when Engineers get together with Accountants to do sales and marketing.

Intel only need 4 desktop processors.

An i3, Dual Core with Turbo Boost - 2.5ghz

An i5, Dual core with Turbo Boost and Hypder Threading 2.5-3.5ghz

An i7, Quad Core with Turbo Boost and Hyper Threading 2.8-3.6ghz

We don't need 6 different versions of the desktop i3, and have you seen how many different versions of the i7 there are, between the mobile and desk top versions it's just stupid.

However, none of that has anything do with whether or not Hyper Threading is worth it or not