Message 83724 - Python tracker

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Author	vstinner
Recipients	pitrou, vstinner
Date	2009-03-18.01:16:10
SpamBayes Score	7.211496e-06
Marked as misclassified	No
Message-id	<1237338972.64.0.602798435318.issue5502@psf.upfronthosting.co.za>
In-reply-to

Content
TextIOWrapper.readline() is much faster (eg. 72 ms vs 95 ms) than BufferedReader.readline(). It's because BufferedReader always acquires the file lock, whereas TextIOWrapper only acquires the file lock when the buffer is empty. I would like a BufferedReader.readline() as fast as TextIOWrapper.readline(), or faster! Why BufferedReader's attributes are protected by a lock whereas TextIOWrapper's attributes are not? Does it mean that TextIOWrapper may crash if two threads calls readline() (or different methods) at the "same time"? How does Python 2.x and 3.0 fix this issue?

TextIOWrapper.readline() is much faster (eg. 72 ms vs 95 ms) than 
BufferedReader.readline(). It's because BufferedReader always acquires 
the file lock, whereas TextIOWrapper only acquires the file lock when 
the buffer is empty.

I would like a BufferedReader.readline() as fast as 
TextIOWrapper.readline(), or faster!

Why BufferedReader's attributes are protected by a lock whereas 
TextIOWrapper's attributes are not?

Does it mean that TextIOWrapper may crash if two threads calls 
readline() (or different methods) at the "same time"?

How does Python 2.x and 3.0 fix this issue?

History
Date	User	Action	Args
2009-03-18 01:16:13	vstinner	set	recipients: + vstinner, pitrou
2009-03-18 01:16:12	vstinner	set	messageid: <1237338972.64.0.602798435318.issue5502@psf.upfronthosting.co.za>
2009-03-18 01:16:11	vstinner	link	issue5502 messages
2009-03-18 01:16:10	vstinner	create