Ozzy, Yes, AmiBroker has the necessary coding to make use of the switch.
If you follow Tomasz's suggestion from an earlier thread, you can modify your boot.ini in such a way that you will be able to go back to your original configuration without any need for other drives, OS's, etc. http://finance.groups.yahoo.com/group/amibroker/message/129542 Mike --- In [email protected], "ozzyapeman" <zoopf...@...> wrote: > > Hmmm. On third thought, it seems that implementing the /3G switch is a > little too risky for my tastes: > > "Before adding the 3GB switch though it is important to note that the > switch is very picky, and requires that every device and driver on your > system be fully WinXP compatible in order to work at all. If anything in > the system is not compatible, Windows will not load at all when > restarting with the 3GB switch activated. The only way to then remove > the switch from the Boot.ini file so that Windows can load is to either > mount the drive in another system and manually change the boot.ini file, > or reformat the drive and re-install Windows. Both solutions are far > from ideal. > > To safely add the 3GB switch we recommend adding a second instance of > the OS in the boot.ini, and add the /3GB switch to that second version. > " > > http://vfxpedia.com/index.php?title=FAQ/3GB_Switch > > > Been through windows-reinstall nightmares before with that sort of > tinkering around. > > So I will just try trimming my databases for now. > > In the future, hopefully AB can allow us to set max symbols to less than > 11 symbols (how about as low as 1?), so that the cache is flushed > earlier. > > > > --- In [email protected], "ozzyapeman" <zoopfree@> wrote: > > > > ...and one more question: I have a number of computers. One runs WinXP > 32 bit, with 32 Bit AB 5.25, which I would test out this /3G boot.ini > switch. > > > > The other PC is running Vista Ultimate 64 bit with same 32 Bit AB > 5.25. Does the /3G switch apply also to VistaU64? If not, what is > recommended on VistaU 64 to manage memory on the AB database in order to > reduce crashes? > > > > > > > > --- In [email protected], "ozzyapeman" zoopfree@ wrote: > > > > > > Thanks. > > > > > > According to this Microsoft page, > > > > > > "Executables that can use the 3-GB address space are required to > have > > > the bit IMAGE_FILE_LARGE_ADDRESS_AWARE set in their image header." > > > > > > http://www.microsoft.com/whdc/system/platform/server/PAE/PAEmem.mspx > > > > > > Can you confirm that Amibroker (broker.exe) has the required info in > > > it's image header? > > > > > > If so, I will try modifying boot.ini with the /3G switch. > > > > > > > > > > > > --- In [email protected], "Tomasz Janeczko" <groups@> wrote: > > > > > > > > There is another method: "max cache size (MB)", > > > > however it only applies when min. 11 symbols is reached. > > > > > > > > You can run your windows with /3G switch in boot.ini > > > > this will give you extra gigabyte of addressable space. > > > > > > > > Best regards, > > > > Tomasz Janeczko > > > > amibroker.com > > > > ----- Original Message ----- > > > > From: "ozzyapeman" zoopfree@ > > > > To: [email protected] > > > > Sent: Friday, May 08, 2009 1:34 AM > > > > Subject: [amibroker] Re: AB Crashes when switching symbols > > > > > > > > > > > > > Tomasz - thanks for the reply. > > > > > > > > > > I am reluctant to use 64 bit AB only because I auto trade and > last > > > time I read, people were having issues with AB 64 bit in this > > > > > regard, and I think you also mentioned to consider that package > as > > > still experimental. > > > > > > > > > > On AB 5.25 32 bit, reducing max. symbols to 11 does not help in > my > > > case, as the 11 symbols in memory are big enough to cause the > > > > > crash. > > > > > > > > > > Would it be possible in the next AB update to somehow allow the > user > > > to limit the cache some other way, i.e. not based on number > > > > > of max symbols but on overall memory usage? It should > automatically > > > flush data from the cache if it starts to approach overload. > > > > > > > > > > In the meantime, I will reduce the length of my historical data, > and > > > see if that helps. > > > > > > > > > > > > > > > --- In [email protected], "Tomasz Janeczko" groups@ > wrote: > > > > >> > > > > >> You simply forgot that Windows 32 bit limits applicaiton space > to > > > 2GB. > > > > >> It does NOT matter how much you have RAM or page file, > > > > >> as long as you run 32 bit app / windows , the application > > > addressable space is 2GB > > > > >> (or 3GB if running /3G switch in boot.ini) > > > > >> > > > > >> http://msdn.microsoft.com/en-us/library/aa366912(VS.85).aspx > > > > >> > > > > >> There is simply NOT enough memory. > > > > >> > > > > >> 1.25GB is size ON DISK. > > > > >> > > > > >> In memory you need way MORE because you need space not only for > > > data, > > > > >> but also for AFL arrays. > > > > >> > > > > >> Not to mention that Windows usually DOES NOT have that much > > > > >> CONTIGUOUS memory available. > > > > >> > > > > >> Use 64 BIT WINDOWS and 64 BIT VERSION of AmiBroker instead > > > > >> http://www.amibroker.com/x64 > > > > >> > > > > >> or ... reduce amount of data if you want to use 32 bit win/app. > > > > >> > > > > >> By the way, this: > > > > >> In-memory cache size (max. symbols): 20000 > > > > >> is completely over the roof. > > > > >> > > > > >> Set it to 11 if you want to use very long intraday histories, > then > > > AmiBroker > > > > >> will flush unused symbols out of RAM. > > > > >> > > > > >> And ALWAYS the latest (i.e. 5.25) as it uses less memory. > > > > >> > > > > >> Best regards, > > > > >> Tomasz Janeczko > > > > >> amibroker.com > > > > >> ----- Original Message ----- > > > > >> From: ozzyapeman > > > > >> To: [email protected] > > > > >> Sent: Friday, May 08, 2009 12:21 AM > > > > >> Subject: [amibroker] AB Crashes when switching symbols > > > > >> > > > > >> > > > > >> > > > > >> > > > > >> Recently I built up my database to include 12 Forex pairs > with > > > historical 1-min data going back 10 years or so on each symbol. > > > > >> The total size of the database is only 1.25 GB, which does not > seem > > > too bad. > > > > >> > > > > >> The problem is that when I switch charts from one symbol to > > > another, I notice that mem usage in windows task manager indicates > > > > >> that AB (Broker.exe) keeps growing by 150mb or so, each time I > > > switch symbols, and does not go down. If I switch symbols 6 or 7 > > > > >> times, AB finally crashes. > > > > >> > > > > >> This is especially cumbersome when I want to Merge each > symbol > > > with the latest weekly historical data. After merging a few > > > > >> symbols, AB crashes. > > > > >> > > > > >> I am running WinXP on a dual quad-core with 8GB RAM, with > > > allowable page file up to 25 GB. The crashes happen on AB 5.24 and > > > > >> 5.25. I imagine the same thing would happen on 5.20 but I have > not > > > reverted that far back. > > > > >> > > > > >> In AB, I have the following set in > > > > >> > > > > >> Tools--> Preferences --> Data: > > > > >> > > > > >> In-memory cache size (max. symbols): 20000 > > > > >> > > > > >> (Max MegaBytes): > 1000 > > > > >> > > > > >> Number of bars to load: 100 > > > > >> > > > > >> > > > > >> AB does not allow me to set max. symbols to any less than 10. > I > > > imagine if I could set that to 1 or 2, that would keep the > > > > >> cache sufficiently low in terms of memory usage. > > > > >> > > > > >> So the question is - what settings do I need to set, in the > Data > > > tab or other tabs, in order to ensure less memory usage to > > > > >> avoid crashes? Again, I only have 12 symbols in the database, > and I > > > imagine many users out there have far more than that. > > > > >> > > > > >> This problem is preventing me from trading more than a couple > of > > > symbols at a time, without running into crashes. > > > > >> > > > > >> Any feedback greatly appreciated. > > > > >> > > > > > > > > > > > > > > > > > > > > > > > > > ------------------------------------ > > > > > > > > > > **** IMPORTANT PLEASE READ **** > > > > > This group is for the discussion between users only. > > > > > This is *NOT* technical support channel. > > > > > > > > > > TO GET TECHNICAL SUPPORT send an e-mail directly to > > > > > SUPPORT {at} amibroker.com > > > > > > > > > > TO SUBMIT SUGGESTIONS please use FEEDBACK CENTER at > > > > > http://www.amibroker.com/feedback/ > > > > > (submissions sent via other channels won't be considered) > > > > > > > > > > For NEW RELEASE ANNOUNCEMENTS and other news always check > DEVLOG: > > > > > http://www.amibroker.com/devlog/ > > > > > > > > > > Yahoo! Groups Links > > > > > > > > > > > > > > > > > > > > > > > > >
