Level Extreme platform
Subscription
Corporate profile
Products & Services
Support
Legal
Français
Low level read-write optimization for very big file
Message
General information
Forum:
Visual FoxPro
Category:
Coding, syntax & commands
Miscellaneous
Thread ID:
00733923
Message ID:
00733943
Views:
20
>Maybe the problem is too much memory, so Windows start swaping VFP memory. Try to limit the memory with SYS(3050). You can also try to issue FFLUSH() comman every few thousand records.
>

I have allready try to fflush at every 10 000 rows with no benefits.

I do not know that there is such thing as "too much memory" :-)
In my mind the more you can put in a box, better the performance will be!
Tomorrow, I will try to reduce the fox memory to see what happen...

Thanks :-)



>>(VFP 7 SP1 on Windows 2000 or Windows XP pro)
>>
>>I have to perform 3 operation on a text file.
>>
>>1 - read a line from a text file.
>>2 - perform some operations on the string.
>>3 - write the line in another file.
>>
>>The text file was really big (950 mb).
>>
>>The program run fast for the first ~50 mb but after that it start to slow down (crawl).
>>The computer have 1 gb of memory an 100 gb of available disk space.
>>From the task manager I can see that only around 200 mb was used during the operation.
>>
>>What is the best way to open the files? buffered/unbuffered?
>>Flush when I reach a certain point in the file? every 10 mb?
>>How can I optimize the process to use all available memory and speed up the process? some sys() function to use?
>>
>>TIA :-)
If we exchange an apple, we both get an apple.
But if we exchange an idea, we both get 2 ideas, cool...


Gérald Santerre
Independant programmer - internet or intranet stuff - always looking for contracts big or small :)
http://www.siteintranet.qc.ca
Previous
Next
Reply
Map
View

Click here to load this message in the networking platform