Message 221095 - Python tracker

Message221095

Author	vstinner
Recipients	Claudiu.Popa, demian.brecht, vstinner
Date	2014-06-20.15:03:11
SpamBayes Score	-1.0
Marked as misclassified	Yes
Message-id	<1403276591.42.0.637676833427.issue21790@psf.upfronthosting.co.za>
In-reply-to

Content
> When sending data, the blocksize is currently hardcoded to 8192. Yeah, same value for io.DEFAULT_BUFFER_SIZE. > It should likely be set to the value of resource.getpagesize(). Could you please elaborate? A page size is 4096 bytes on my Linux. So your page double the number of calls to read(), right? shutil.copyfileobj() uses a buffer of 16 KB by default. See also the issue #21679 which adds a private copy of the stat().st_blksize attribute in a FileIO object.

Content

> When sending data, the blocksize is currently hardcoded to 8192.

Yeah, same value for io.DEFAULT_BUFFER_SIZE.

> It should likely be set to the value of resource.getpagesize().

Could you please elaborate? A page size is 4096 bytes on my Linux. So your page double the number of calls to read(), right?

shutil.copyfileobj() uses a buffer of 16 KB by default.

See also the issue #21679 which adds a private copy of the stat().st_blksize attribute in a FileIO object.

History
Date	User	Action	Args
2014-06-20 15:03:11	vstinner	set	recipients: + vstinner, Claudiu.Popa, demian.brecht
2014-06-20 15:03:11	vstinner	set	messageid: <1403276591.42.0.637676833427.issue21790@psf.upfronthosting.co.za>
2014-06-20 15:03:11	vstinner	link	issue21790 messages
2014-06-20 15:03:11	vstinner	create