From mboxrd@z Thu Jan  1 00:00:00 1970
From: Petr Vorel <pvorel@suse.cz>
Date: Fri, 16 Apr 2021 15:10:07 +0200
Subject: [LTP] [PATCH v3 1/2] splice02: Generate input in C
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Hi Cyril,

...
> > Maybe one more change: INT_MAX is a bit too much, it timeouts.
> > I'll use 262144 as max allowed -n (the default on intel - 2x max pipe size).

> I guess that the main problem here is that we write one character at a
> time, which means that we spend most of the time in syscall handler code
> rather than copying the data. It may work much better if we change the
> code to write 512 bytes at a time. I.e. something as:

Sounds very reasonable, thx! I'll send v4.

Kind regards,
Petr

> 	#define BUFSIZE 512

> 	char buf[BUFSIZE];

> 	memset(buf, 'a', BUFSIZE);

> 	while (to_write > 0) {
> 		size_t size = to_write > BUFSIZE ? BUFSIZE : to_write;

> 		...

> 		to_write -= written;
> 	}