X-Recipient: archive-cygwin AT delorie DOT com
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 5CD613876057
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cygwin.com;
	s=default; t=1584847309;
	bh=khQ2uMkGlviGCdlTGKP97om5r6c6wDL0Ich8ErvSTRQ=;
	h=Date:To:Subject:List-Id:List-Unsubscribe:List-Archive:List-Post:
	 List-Help:List-Subscribe:From:Reply-To:From;
	b=mDVdZjOw2H7TasHeiUsZN8FtdXN7SdzoL5Qrbs9ffeLecogCpJvBiqA5mh4KTf358
	 S3hGS4HudBZ7dr0EbHgCxLRBHN2BKW6HbmAceGYaavvMVL0ahi43zRMuKjyvvxKxOj
	 tbdWX9IcI8CC4Ew904a/4wwVCWWlHY72tYU5WI/c=
X-Original-To: cygwin AT cygwin DOT com
Delivered-To: cygwin AT cygwin DOT com
DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org E7854385BF9F
Date: Sun, 22 Mar 2020 03:21:35 +0000
To: "cygwin AT cygwin DOT com" <cygwin AT cygwin DOT com>
Subject: New pty implementation is really slow
Message-ID: <T2ea_w0xYVfOjY80lzLI17-jZsISnTZXfTh_jqEePHLNtgG2TCVMAovKFkBIEKhISLr9GFOIKSUixMgWa72iiqZLCDUCXVCJbAy3w7DGphU=@protonmail.com>
MIME-Version: 1.0
X-Spam-Status: No, score=-4.6 required=5.0 tests=BAYES_40, DKIM_SIGNED,
 DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, FREEMAIL_FROM, RCVD_IN_DNSWL_LOW,
 SPF_HELO_PASS, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2
X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on
 server2.sourceware.org
X-BeenThere: cygwin AT cygwin DOT com
X-Mailman-Version: 2.1.29
List-Id: Cygwin mailing list <cygwin.cygwin.com>
List-Archive: <http://cygwin.com/pipermail/cygwin/>
List-Post: <mailto:cygwin AT cygwin DOT com>
List-Help: <mailto:cygwin-request AT cygwin DOT com?subject=help>
List-Subscribe: <http://cygwin.com/mailman/listinfo/cygwin>,
 <mailto:cygwin-request AT cygwin DOT com?subject=subscribe>
From: Joe via Cygwin <cygwin AT cygwin DOT com>
Reply-To: Joe <joeworth AT protonmail DOT com>
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
Sender: "Cygwin" <cygwin-bounces AT cygwin DOT com>

I'm using cygwin 3.1.4 on Windows 10.

The new pseudo terminal stuff seems really slow.

For example:
$ time seq 10000
(output omitted)
real    0m23.510s
user    0m1.515s
sys     0m4.483s

If I minimize the mintty window while seq is running, it gets slightly better:
real    0m4.562s
user    0m0.390s
sys     0m1.202s

But when I set CYGWIN=disable_pcon before starting mintty, I get:
$ time seq 10000
(output omitted)
real    0m0.366s
user    0m0.109s
sys     0m0.093s

So the new implementation seems to be over 60 times slower than the old one.
--
Problem reports:      https://cygwin.com/problems.html
FAQ:                  https://cygwin.com/faq/
Documentation:        https://cygwin.com/docs.html
Unsubscribe info:     https://cygwin.com/ml/#unsubscribe-simple