Multithreaded operation

so - have mac 4 core intel i7 cpu (with 4 additional "simulated" cores). software uses cores extremely fast in cpu intensive operations, video compression.

 

this makes me wonder why lightroom doesn't seem use of processing capability, when it's cpu intensive well?

 

importing photo set , rendering previews working on multiple photos @ same time (and rendering start right after first photo has been imported), , eat more 1 core while doing that. instead, what's happening is, lightroom can peak @ around 60% of cpu use (of available 800%), , disk usage (in bytes/second) never reaches anywhere near peak performance of computer.

 

i have no idea performance limits come from, i'd appreciate if lr team looked multithreaded optimizations speed software. computers scaling performance adding cores, should take account in software design well.

i appreciate viewpoint , little surprised , disappointed performance on windows 7 64bit i7 8g rig v.good graphics card , have no idea performance limits are, have sympathies - multi-threading programming technique , architecture still in infancy , doing accommodate lowest common specifications must quite hard lr team. 

 

that said, bibble team seems on performance wise both marketing , own b5 trial experience... although did take them 2 years re-architect sw seems have p'd off few of customers.  must have found clever approach max usage of available crunching cycles either through multi-cpu usage, mmx etc or perhaps gpu itself.

 

anyway question of multi core usage in lr... i'm no expert , did think did limited use of cores, curiosity did go further , using basic windows tools clear me operations, example moving of sliders , down in develop mode 1:1 view, lr did spawn 8 new threads...

 

 

however until i7 processor level 1 cache size gets 64kb more size of raw file 25mb suspect never see 100% cpu usage across processors image developing, things limited main memory bandwidth.  of course depends how mem io v's maths going on ... suspect noise reduction has - each pixel, @ neighbours requirement ... mem io high despite maths, , ok clever thread division can devised maximise cache hits, suspect complex allow combinations of number of cpu's cache size etc.   in short ... complicated i'm guessing.

 

if during publishing number of photo's hard disk, appears me multi-threading being employed, suspect import not tried ...

but again these threads competing disk io on 25mb raw's , network bandwidth nas box.

 

in summary, multi-threading appears employed @ both micro pixel level , macro task level.

 

as aside, might little unfair compare current video performance lr may have do, , sure graphics card not involved in video compression performance mention?   have been doing video processing coding - example real time filtering hd camera feeds in hsv space of done on graphics card 800 processing units - not expect @ resolution on cpu(s) in real time.  suspect not possible fit whole lr rending pipeline on g. card - ahhh... day be!

 

anyway, of above complete rubbish, i'm no expert, don't forget lr has accommodate lower spec older machines , plenty of photographers use laptops in field - whilst find performance little lack lustre (worse others guess), have degree of sympathy lr team.

 

alan.

 

ps - i'm left wondering contant 42 ish lightroom threads doing!     "deep thought" perhaps?

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