i have a 3 gig memory in my machine and installed ab when i had 2 gig of memory on it. it set the cache to 209. i just changed it to 1 gig 33% of my memory.
--- In [email protected], "Tomasz Janeczko" <[EMAIL PROTECTED]> wrote: > > By default is it set to half of available physical memory. > 409MB should be just fine in your case. > > Best regards, > Tomasz Janeczko > amibroker.com > ----- Original Message ----- > From: "danielwardadams" <[EMAIL PROTECTED]> > To: <[email protected]> > Sent: Thursday, May 15, 2008 3:26 PM > Subject: [amibroker] Re: Dual-core vs. quad-core > > > > Tomasz, > > I'm sure you've answered this before but I couldn't find it. How do > > you best determine AB internal cache size? I see mine is set at > > 409MB. Other database settings are 10000 symbols (even though I never > > have over 200-300 in my database), number of bars to load is 1000, > > limiting number of saved quotations isn't checked. > > > > I'm running an Athlon 3200+ processor, Windows XP SP2, and AB 5.09.0. > > I have 2GB and rarely use much over half of it. I'm mostly interested > > in speed while optimizing formula parameters with Quotes Plus EOD > > data using the Intelligent Optimizer (IO). I have one long run on the > > weekends that I'd be (very) interested in speeding up > > > > Thanks, > > Dan > > > > > > --- In [email protected], "Tomasz Janeczko" <groups@> > > wrote: > >> > >> Hello, > >> > >> As for 1) you would do better by increasing AB internal cache in > > preferences. > >> > >> Best regards, > >> Tomasz Janeczko > >> amibroker.com > >> ----- Original Message ----- > >> From: "akerstkh" <khtangkh@> > >> To: <[email protected]> > >> Sent: Wednesday, May 14, 2008 6:09 PM > >> Subject: [amibroker] Re: Dual-core vs. quad-core > >> > >> > >> > Good morning, > >> > > >> > Just to share some experience in Optimizing the Speed... Mainly > > in > >> > compiling of data with the ATC instruction with loops... > >> > > >> > 1) Created a RAM Disk of 1G. Copy the Data Folder to the RAM > > Disk > >> > and then use the Data in the RAM Disk do the compiling. (Only > > worth > >> > doing if compile a couple of times a day.. It cut down from 16 > > mins > >> > to 11 mins. ) > >> > > >> > 2) MOVE the Data Folder to another physical drive. Then perform > > the > >> > disk defragmenter on the Amibroker Drive a couple of times. Then > >> > MOVE the Data Folder back to the original position. > >> > > >> > 3) Chop Down the number of bars in Data Base. > >> > > >> > > >> > > >> > > >> > The Current system is Intel Core 2 @2.13GHz with 4G RAM. > >> > > >> > Yet to try is to upgrade the system with RAID4 with 4 Disks and > >> > Q9450. > >> > > >> > Is there any one can comment on the experience with RAID5 > > system? > >> > > >> > > >> > Best Regards > >> > KH Tang > >> > > >> > > >> > --- In [email protected], Dennis Brown <see3d@> wrote: > >> >> > >> >> It also makes me wonder if there is another possibility for > > speed > >> >> optimization. I run more than 1 RT chart at the same time to > > get > >> >> multi-timeframe results that are not possible in a single chart - > > - > >> > then > >> >> pass results between the charts. It seems as though parallel > >> >> processing would be possible between multiple "live" indicator > >> > mode > >> >> charts. Maybe I will have to get the 8 core system next time :) > >> >> > >> >> Best regards, > >> >> Dennis > >> >> > >> >> On May 14, 2008, at 10:13 AM, dloyer123 wrote: > >> >> > >> >> > Interesting result. It is reasonable to expect newer and > > future > >> >> > processors to have even larger caches. 6MB on the E8400 > >> >> > > >> >> > So, there may be an opportunity to get useful work out of the > >> > other > >> >> > cores during long optimization runs. Maybe large "work units" > >> > such > >> >> > as symbols lists or entire optimization passes to minimize sync > >> >> > overhead? > >> >> > > >> >> > That also implies that user formula code could be optimized if > > we > >> >> > group array access together, ie use a result right after it is > >> >> > created, so it can be pulled out of cache, rather than wait > > until > >> >> > later in the code. I will have to try this... > >> >> > > >> >> > > >> >> > > >> >> > --- In [email protected], "Tomasz Janeczko" <groups@> > >> >> > wrote: > >> >> >> > >> >> >> Hello, > >> >> >> > >> >> >> I just run the same code on my relatively new notebook (Core > > 2 > >> > Duo > >> >> > 2GHz (T7250)) > >> >> >> and the loop takes less than 2ns per iteration (3x speedup). > > So > >> > it > >> >> > looks like the data sits entirely inside the cache. > >> >> >> This core 2 has 2MB of cache and thats 4 times more than on > >> > Athlon > >> >> > x2 I got. > >> >> >> > >> >> >>> If what you say is true, and one core alone fills the memory > >> >> >>> bandwidth, then there should be a net loss of performance > > while > >> >> >>> running two copies of ami. > >> >> >> > >> >> >> It depends on complexity of the formula and the amount of > > data > >> > per > >> >> > symbol > >> >> >> you are using. As each array element has 4 bytes, to fill 4 > > MB of > >> >> > cache > >> >> >> you would need 1 million array elements or 100 arrays each > > having > >> >> > 10000 elements > >> >> >> or 10 arrays each having 100K elements. Generally speaking > > people > >> >> > testing > >> >> >> on EOD data where 10 years is just 2600 bars should see speed > > up. > >> >> >> People using very very long intraday data sets may see > >> > degradation, > >> >> > but > >> >> >> rather unnoticeable. > >> >> >> > >> >> >> Best regards, > >> >> >> Tomasz Janeczko > >> >> >> amibroker.com > >> >> > > >> >> > > >> >> > ------------------------------------ > >> >> > > >> >> > Please note that this group is for discussion between users > > only. > >> >> > > >> >> > To get support from AmiBroker please send an e-mail directly to > >> >> > SUPPORT {at} amibroker.com > >> >> > > >> >> > For NEW RELEASE ANNOUNCEMENTS and other news always check > > DEVLOG: > >> >> > http://www.amibroker.com/devlog/ > >> >> > > >> >> > For other support material please check also: > >> >> > http://www.amibroker.com/support.html > >> >> > Yahoo! Groups Links > >> >> > > >> >> > > >> >> > > >> >> > >> > > >> > > >> > > >> > ------------------------------------ > >> > > >> > Please note that this group is for discussion between users only. > >> > > >> > To get support from AmiBroker please send an e-mail directly to > >> > SUPPORT {at} amibroker.com > >> > > >> > For NEW RELEASE ANNOUNCEMENTS and other news always check DEVLOG: > >> > http://www.amibroker.com/devlog/ > >> > > >> > For other support material please check also: > >> > http://www.amibroker.com/support.html > >> > Yahoo! Groups Links > >> > > >> > > >> > > >> > > > > > > > > ------------------------------------ > > > > Please note that this group is for discussion between users only. > > > > To get support from AmiBroker please send an e-mail directly to > > SUPPORT {at} amibroker.com > > > > For NEW RELEASE ANNOUNCEMENTS and other news always check DEVLOG: > > http://www.amibroker.com/devlog/ > > > > For other support material please check also: > > http://www.amibroker.com/support.html > > Yahoo! Groups Links > > > > > > >
