How much memory used by a name

[Bruno Desthuilliers]

Bernard Lebel a écrit :
> Diez: thanks, I will try that. However isn't sum() returning an
> integer that here would represent the number of elements?

Nope, it will return the sum of the length of the lines in the list. The 
long way to write it is:

total = 0
for line in thelist:
   total += len(line)


> 
> Bruno: good question. We're talking about text files that can have
> 300,000 lines, if not more. Currently, the way I have coded the file
> writing, every line calls for a write() to the file object, 

Seems sensible so far...

>  The file is on the network.

Mmm... Let's guess : it's taking too much time ?-)

> This is taking a long time,

(You know what ? I cheated)

> and I'm looking for ways to speed up this
> process. I though that keeping the list in memory and dropping to the
> file at the very end could be a possible approach.

OTOH, if the list grows too big, you may end up swapping (ok, it would 
need a very huge list). A "mixed" solution may be to wrap the file in a 
"buffered" writer that only perform a real write when it's full. This 
would avoid effective i/o on each line while keeping memory usage 
reasonable. Another one would be async I/O, but I don't know if and how 
it could be done in Python (never had to manage such a problem myself).

My 2 cents...