Hi, Windows 2000 is a lean OS compared to XP... if you use 2 disks in your system placing vhd file on secondary HD can have a huge impact as well.
Y -------------------------------------------------- From: "Paul Ho" <[email protected]> Sent: Thursday, February 26, 2009 3:24 AM To: <[email protected]> Subject: [amibroker] Re: AmiBroker speed-up in virtual machine!?!? > Markus > It depends on how much data is being cache, whether Ab needs to go > and retrieve any information. anti-virus, sometimes even scanning > stuff in memory. the most reliable way is to completely de-install > your anti- virus and do the test again. --- In > [email protected], "markhoff" <markh...@...> wrote: >> >> >> Hi Tomasz, >> >> during the benchmark I made sure that all data is in the AB cache > (by >> rerunning multiple times, 1st run after AB start is ~30% slower > than >> subsequent runs), therefore anti-virus should not be the reason. I >> just checked this by switching AV off on the native machine, the >> result was the same as before, the VirtualBox is still much > faster. I >> think disk fragmentation is same story, as long as the data is > cached >> it should not have an negative impact ... >> >> Best regards, >> Markus >> >> --- In [email protected], "Tomasz Janeczko" <groups@> > wrote: >> > >> > Hello, >> > >> > Disk fragmentation or lack of antivirus on virtual machine. >> > Most probably your virtual machine >> > has been freshly created and the "virtual hard drive" file >> > is not fragmented. >> > Second reason is anti-virus. Antiviruses intercept all file >> > accesses (they hook into system libs) >> > and they are known to slow down file acces >> > as much as 2-3 times. >> > >> > Best regards, >> > Tomasz Janeczko >> > amibroker.com >> > ----- Original Message ----- >> > From: "markhoff" <markhoff@> >> > To: <[email protected]> >> > Sent: Thursday, February 26, 2009 12:42 AM >> > Subject: [amibroker] AmiBroker speed-up in virtual machine!?!? >> > >> > >> > > >> > > Hi folks, >> > > >> > > I have setup a virtual machine (VirtualBox) to have my real > account >> > > trading with IB separated from other tasks. The strange thing > is that >> > > AB runs in the virtual machine much faster than on the native > hardware >> > > (opposite to my expectation that usually virtual machines have > a >> > > performance penalty), but I have no idea why there is this huge >> > > difference. >> > > >> > > Configuration: >> > > Native machine: Pentium 4, 2.6GHz, 1.5GB RAM, Windows XP SP3 + > usual >> > > tools like antivirus, firewall etc. >> > > VirtualBox: 512MB RAM, Windows 2000 SP2, naked installation >> > > >> > > AmiBroker directory was copied 1:1 from native machine to > virtual >> > > machine, I checked that all preferences are the same. >> > > >> > > Benchmark: Backtesting on Russell 1000 watchlist >> > > native machine: 32s >> > > virtual machine: 20s >> > > >> > > Wow! It looks like something on the native machine is > drastically >> > > reducing the speed of AB, but I have no clue about the root > cause. >> > > >> > > Did somebody observe the same? Any ideas? >> > > >> > > Thanks in advance and best regards, >> > > Markus >> > > >> > > >> > > >> > > >> > > ------------------------------------ >> > > >> > > **** 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 >> > > >> > > >> > > >> > >> > > > > > ------------------------------------ > > **** 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 > > > >
