Re: [amibroker] Speed the database!?, AmiBroker Email List Archive

Hi Tomasz,

It is not every symbol that takes that long. It is very strang. For some symbols or at some time, scrolling is ok, but then with other symbols it really takes forever to scroll. BTW, also switching between tabs is long. I want to click on one of the tabs, and then I have to wait for 4-5 seconds, then I want to scroll (on this tab there is only price and portfolio, so it is not because of the formula).

Is it because the tickers were imported from Metastock format? I never had this problem before, but also I did not have a 8000 tickers database with 1-minute 1 year long data back then.

If it was because of a virus, the problem would have been the same before, right?

Of course it is worse when I am optimizing. I guess this is normal?

Thanks,

Louis

2008/7/21 Tomasz Janeczko <groups@xxxxxxxxxxxxx>:

Hello,

Here is a video showing scroll speed:

http://www.amibroker.com/video/ScrollSpeed.wmv

Data source: eSignal, 80000 quotes, 1-minute interval and hourly interval.

Scrolling and zooming *is* immediate as shown in the video,

it is not really coupled with data source used as data are in RAM anyway.

Best regards,
Tomasz Janeczko
amibroker.com

----- Original Message -----

From: Louis Préfontaine

To: amibroker@xxxxxxxxxxxxxxx

Sent: Monday, July 21, 2008 1:54 AM

Subject: Re: [amibroker] Speed the database!?

Hi Tomasz,

I thought that once I imported Metastock files the data was going into my AB database. In fact, when I manually open AB database's folder, I see each and every ticker. Are you sure the data is in the Metastock files at that point? (The speed issue is not in Real-time, but in my database that goes from last July till last week).

Scrolling is not immediate in my AB, even for charts with only price and MA and portfolio equity. It takes some time to lead when I scroll.

I defragmented my hard drive, but still it is slow...

Any idea?

Thanks,

Louis

2008/7/20 Tomasz Janeczko <groups@xxxxxxxxxxxxx>:

No, they are NOT in AB local database. QCollector stores data into Metastock databases and you

are accessing external MS database.

Also scrolling is *immediate* for any formula shipped with AB.

If it is not on your end, it means that you are using

some formula of your own writing (or downloaded from somewhere) that takes forever

to execute.

Faster? Use AmiBroker own IQFeed plugin, without man-in-the-middle (QCollector).

Still MS database should be fast enough, if it is not - it means that your hard disk is badly fragmented.

Best regards,
Tomasz Janeczko
amibroker.com

----- Original Message -----

From: Louis Préfontaine

To: amibroker@xxxxxxxxxxxxxxx

Sent: Sunday, July 20, 2008 4:05 PM

Subject: Re: [amibroker] Speed the database!?

Also, when I right-click to change the time displayed, it takes 3-4 seconds and lot of loading... Any way to speed this?

Thanks,

Louis

2008/7/16 Louis Préfontaine <rockprog80@xxxxxxxxx>:

Hi Tomasz,

I am using data that has already been downloaded with QCollector. Hence, I am running on a local database and what takes like 3-4 seconds is scrolling through the 1-minute bars. Let's say it is Day 1 at 11:00 and I want to scroll back to Day 0, I use my mouse wheel but for 3-4 seconds the images does not move at all, then I hear my computer loading, then I see the bars before. Is there a way to make that faster?

Thanks,

Louis

2008/7/15 Tomasz Janeczko <groups@xxxxxxxxxxxxx>:

Hello,

No, it does NOT take 3-4 seconds to load each ticker. Loading (i.e. switching between symbols) is INSTANT.

It takes 3-4 to BACKFILL. That's huge difference.

Are you aware that you are on 256kbps connection. That means that your fully saturated connection is able

to deliver about 25KB of data per second. Now do you have any idea how much data is one day

of 1-minute data?

As far as I remember you are using IQFeed. It delivers data in ASCII format.

Let's say single quote line is 100 bytes. Compressed it is 50. Now there are 60 lines per minute and

480 lines per 8 hours. That's 24KB PER DAY PER SYMBOL of 1-minute data. That means

that it takes 1-second FULLY SATURATED your internet connection to deliver 1-day worth of 1-minute data for one symbol.

That's physical limit of your internet connection.

Yes there is a way to get it faster:

a) invest in better internet connection

b) subscribe to data source that allows those 500 symbols to be streaming

c) run scan with wait for backfill PRIOR to market open. Once you initialy scan all symbol

UNCHECK "wait for backfill" and scans will fun blazing fast.

Best regards,
Tomasz Janeczko
amibroker.com

----- Original Message -----

From: Louis Préfontaine

To: amibroker@xxxxxxxxxxxxxxx

Sent: Monday, July 14, 2008 11:02 PM

Subject: [amibroker] Speed the database!?

Hi,

I have my 1-minute database setted with all my tickers and everything, but damn it it is so slow! It takes like 3-4 seconds to load each ticker... Is there a way to make it run faster, considering I don't need all the data when exploring?

Thanks,

Louis