Does Lightroom run faster on a PC?

[sheldonnalos]

<p>I was reading an excellent article recently by Lloyd Chambers about optimizing Lightroom setup for use on a Mac. (http://macperformanceguide.com/Optimizing-Lightroom.html#PerformanceTips) He raises an interesting point about how much of the computing power of his Mac Pro goes unused by Lightroom because it does not efficiently use all of the CPU cores for batch operations. <br /> <br /> I've noticed previously that the activity monitor on my PC seemed to show pretty good usage of all CPU cores during import/export so it occurred to me that the PC version of Lightroom might be better optimized than the Mac version of Lightroom.</p>

<p>I wanted to see how efficiently my computer used its CPU so I replicated Lloyd Chamber's tests from the article <em> (keep in mind that we are comparing a current top of the line $6k Mac Pro with a moderately quick $1k home build PC)</em> . The tests were to do the following:</p>

<p>1) Import 128 RAW files from a 1Ds Mark III (add to catalog without moving and render 1:1 previews)<br>

2) Export 128 full quality JPG files from 1Ds Mark III RAW files.</p>

<p>Lloyd's current generation Mac Pro 2.93Ghz 8 Core (dual quad core) with 32GB RAM did <strong>Test 1 in 603 seconds</strong> and did <strong>Test 2 in 351 seconds</strong> .<strong></strong><br>

<strong><br /> </strong> My PC running Vista Home Premium 64bit with a Q9950 Intel quad core processor at 3.6Ghz with 8GB of RAM did <strong>Test 1 in 313 seconds</strong> and did <strong>Test 2 in 306 seconds</strong> .<br>

<br /> The activity monitor showed that all 4 cores on my system stayed at above 50% usage the entire operation, suggesting to me that the PC version does a much better job of using all the CPU cores. The difference in speed for importing/rendering previews was particularly surprising to me with the PC performing almost twice as fast as the Mac Pro. On the export side, the difference might be more about clock speed than CPU usage since the proportional difference is about the same.<br>

<br /> Is there a reason that Lightroom runs faster on the PC? Is it due to the 64bit Vista OS? Is it the underlying code in how Lightroom is compiled for PC? I'm not bashing Macs here (I own one), just hadn't seen this issue raised before.</p>

[martin_howard1]

<p>Very few applications are designed to make use of multiple cores efficiently (yet), most developers have only just got to grasps with dual core architectures.<br>

Certainly in a lot of cases a higher clock speed vs more cores (with the same processor architecture) will win the benchmarks.<br>

It's a hard one to call though, and is certainly not really down to mac/pc differences, that would account for very little in these sort of cpu intensive operations.</p>

[peterbcarter]

<p>If your 4 cores were being used at %50, it only suggests that it used only 1/2 of your processors.</p>

<p>Lightroom really is Memory and IO bound. You have enough memory for that not to be an issue. Your CPU is almost %20 faster, which is considerable. His are xeons, so IO should be faster. The questions would be, what kind of drives were used? External USB/Firewire drives are slow on IO compared to scsi,eide,sata.</p>

<p>Another consideration would be the size of the catalog. Once it reads the records, it tosses them in memory. Bigger catalog means larger resources and drive IO.</p>

<p>I have a G4 1.3 ghz/1.25 gig ram mac ibook. I also have a Quad 2.3 amd/4 gig ram Vista/64 box with a drive array that gives me 140mb/s drive io. There are some things my ibook does that is not too bad, but is limited to the drives plugged into the usb/firewire port. The latter is why I got a PC. I can say CPU/Multi core is of the least influential that Lightroom wants. More ram does not make a difference unless there is not enough. It loves fast drives.</p>

<p>Keep this in mind and re-look at the setups to determine what made what faster or slower. It's really not a Mac/Pc thing as opposed to just a hardware thing.</p>

[sheldonnalos]

<p>I'm not calling this a Mac vs PC thing, I'm calling it a poor implementation on the part of Adobe for how effectively Lighroom uses the CPU on the different platforms. I'm certainly open to the idea that this is something more than that, but I don't know what it would be yet.</p>

<p>I don't think this would be an IO or hard drive issue. If you read the details on his test, he did it with both an SSD drive and a 4 drive RAID 0 SATA array with no difference. He also monitored read/write demands on the drive and they were very low, not the limitation in this test. On the export side of things, his tests showed that drive speed didn't matter until you started exporting very big files (16 bit uncompressed TIF files).</p>

<p>My catalog is moderate sized, roughly 8000 images. Don't know how big his catalog is or how much that would come into play. I doubt it would come close to accounting for the 100% difference in performance in importing and rendering 1:1 previews.</p>

<p>I've found that Lightroom is not very RAM hungy beyond about 2GB, even with heavy batch processing operation. It certainly does tax the CPU quite a bit for major things such as adjustment brushes, gradient tool, healing brush and when rendering previews or exporting photos.</p>

<p>In regard to the setups, his computer is vastly superior to mine in every major category (# of CPU cores, IO and disk speed, RAID 0 array, SSD disk, 4 times the RAM, etc.) except for pure clock speed. For example on some of his demanding photoshop benchmark tests that are scratch disk dependent, his machine is faster than mine by a factor of 10x. My machine should not be faster than his at anything other than single core CPU tasks, and then it should only be 20% faster, not 100% faster.</p>

<p>I think the thing that stood out to me as the cause was CPU usage. His primary complaint in the article is that his Mac Pro used only about 20% of his CPU processing capability when importing and rendering 1:1 previews. I would estimate that my CPU usage was about 75% of all 4 cores in total on importing and rendering 1:1 previews. I would think that this has to be rooted in either how the 64 bit version of Lightroom is optimized, or in the way that the PC version is encoded in general. Importing and exporting are the two biggest things that I have to wait for in Lightroom, and it's a shame that a mid tier PC can even come close to a top of the line Mac Pro.</p>

<p>Assuming that it is rooted in the software and not a 32bit vs 64bit thing, I don't understand why Adobe would have the Mac version of LR be so much more inefficient than the PC version.</p>

[Ed_Ingold]

<p><em>If your 4 cores were being used at %50, it only suggests that it used only 1/2 of your processors.</em></p>

<p>Windows Task Manager (a system utility) shows the load placed on each separate processor in addition to the overall load. You can see at a glance how the load is distributed, which is central to how the application and operating system make use of available resources. A multi-core processor does make a difference in the performance of Lightroom, which renders images about 4x as fast in my octoprocessor Xeon workstation as in my dual-processor P4. I use the same external USB2 drives with both computers. I run 32-bit XP for maximum compatibility with Adobe applications.</p>

<p>I suspect Lightroom and Photoshop run better under Windows because they were originally written for Windows, but not for 64-bit. In this case, Mac runs Lightroom in a virtual workspace rather than as a native application - convenient, but not the best way to do things. Whoops, I meant to say Mac's way is the best of all possible ways. Mea culpa.</p>

[peterbcarter]

<p>Sheldon, I am in agreement of what you are saying. Just don't assume the hardware is superior on the Mac. I have both, and I had a Mac before I had a PC. Yes, my macs had 64 bit busses and 64 bit os's before PC's. I can tell you they sucked, and didn't get better very fast. My G4 Tower (Mac Pro of it's day) constantly suffered from bus-lock. Put in a 64 bit gig net card and watch it freeze. Ask anyone who had a PPC(pre g3) and they can tell you how many crashes they had per hour; the adds don't mention that. Apple designs can be leading edge at the time of design, but they don't update as fast as PC's. My guess is that your PC has newer everything on board than the Mac Pro. I'm not saying that Apple does not make beautiful hardware - they do. Just don't get caught in that myth. If you compared that Pro to something in it's hardware class, you would see it fall a bit short. Point is, yours did and you didn't (I assume) pay 3-4k for your pc.</p>

[kelly_flanigan1]

<p>Edward and the fine group here;</p><p> Photoshop actually was originally only for the Mac; and NOT available for the PC. </p><p>Us PC users used Photostyler; or used the dark side ie a Mac.</p><p> This was with photoshop versions 1 and 2. About version 2.5 or so a Photoshop version came out for the PC ; it had poor performance at first; ; later it was fixed before version 3. The first version of Photoshop that ran on a PC was version 2.5 (Brimstone) ; it had a poor performance compared to 2.5 Photoshop for the Mac; ie (Merlin). By version 3 one had layers and decent performance with a PC. To show how long ago this all was; a dream machine I bought for Photoshop 3.0 was 3 grand; a 90Mhz Pentium with a trick HDA contioller; an ultra fast high through put hda; a 3800rpm one. I got a single 16meg ram chip; it cost the same as the 17" CRT; same as Photoshop 3.0; which installed with floppiess.</p>

[peterbcarter]

<p>But you did not have to wrestle with corrupted fonts like the mac guys.....lol</p>

[Ed_Ingold]

<p><em>Photoshop actually was originally only for the Mac; and NOT available for the PC. </em></p>

<p>Yes, and cars originally came equipped with buggy-whip holders (in case of a tow, not unusual even in the 30's). Historical interest aside, Photoshop has been written for the PC since version 7 and ported to the Mac as an afterthought. Premiere (video) and Lightroom are written strictly for the PC since there is little to be gained competing against their Mac-only counterparts. Perhaps it has something to do with the overall 20 to 1 dominance of PCs over Mac, and a 4 to 1 share of new purchases in the graphics business.</p>

[kelly_flanigan1]

<p>Photoshop also supports dual CPU'S and dual cores since version 4.0 ie 1996. Thats when we built up dual CPU 200Mhz PPros here as our power machines for photoshop. Peeking at task manager and seeing if the other guy/cpu/now core is actually helping/working is thus also "buggy wip" old hat' ancient history; it has been done now for 13 years. Thus folks new to photoshop seem to think that usage of more than one cpu or core is new to photoshop; or believe it helps in all cases.<br>

Dual cpu support in photoshop was around in 1996; when photo.net was just born. As mentioned over the last 13 years; having multiprocessor/core support in photoshop doesnt help with all features; somethings it does nothing; some abit. Newer versions than photoshop 4 of 1996 add more dual/quad support. A 1996 box with four 200Mhz Cpus used more than 2 cores with photoshop 4 in a few cases; thus this is not new either. Rotating a105 meg image on the 1996 box with photoshop 4 takes 9 seconds with one cpu; 7 with two; not a 100 percent gain.<br>

In some of OUR custom batch operations with a modern quad box; vista 64 bit and CS4; only ONE core is used; the others are boobs on a boar hog. Thus beware that since we have run out of CPU speeds over the last 5 years; adding more cores is a cool marketing gig; it helps with many features; and helps others little. Run your own experiements and see what works.</p>