TString and ResizeIncrement

ROOT
1

Hello.

Recently a nice modification was done in TString to be optimized for short strings.
However, it looks to me that a feature to set resize increment was removed.

I am using TString to generate C++ source code, and the code can be as large as several MB. The size is not known a priori; I generate the code by adding lines one-by-one.
With ROOT 5.28 or older, I set the increment to be 32k, and it works fine.
On the other hand, I couldn’t find a corresponding function in the new TString; as a consequence, my generation program became 15 times slower.

Is there a method to set the increment for the new TString .

If not, are there some plans to modify TString for the next release to improve performance for long strings ?
(For example, always increase capacity at least twice of current size.)

Best regards,

Ryu

2

Hi,

I see the issue and will change the algorithm. The current ResizeIncrement() is a static which is not what you want in a threaded environment. I’ll let you know when I’ve made the change.

Cheers, Fons.

3

Hi Ryu,

I’ve improved the TString resize algorithm in the trunk. Please try and let me know how it works now.

Cheers, Fons.

4

Hi.

The new TString is very fast for long strings too.

Thank you.

Ryu