From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id 40CB23858004; Tue, 21 Mar 2023 15:29:52 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 40CB23858004 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1679412592; bh=WXN4cb1aSfJwXpwICfnSW8QcuDIffJLLQGuHEE3nBuQ=; h=From:To:Subject:Date:In-Reply-To:References:From; b=N+mCj/uS0bX+9SguPnSBRHGg7yz3kjdjDcRcGeafy5jVu7CTVApmckkPR4DlyigsH aJ1g2hCAyhiQDp5am0L3nIXfXlrXdHNLJ+OpHyixbgFWEkzzk8dv6O9nEkV1NLj6HY A6CxvR2dxRVZ5YQXowrWt/bWWfJ/vAn0Q+ixAk0A= From: "bruno at clisp dot org" To: glibc-bugs@sourceware.org Subject: [Bug time/30200] time sometimes appears to go backwards Date: Tue, 21 Mar 2023 15:29:51 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: glibc X-Bugzilla-Component: time X-Bugzilla-Version: 2.35 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: bruno at clisp dot org X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Resolution: X-Bugzilla-Priority: P2 X-Bugzilla-Assigned-To: unassigned at sourceware dot org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://sourceware.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 List-Id: https://sourceware.org/bugzilla/show_bug.cgi?id=3D30200 --- Comment #13 from Bruno Haible --- (In reply to Adhemerval Zanella from comment #12) > So this problem *always* existed >From "This problem always existed" you cannot imply "This problem never cau= sed trouble, otherwise it would have been reported". In https://sourceware.org/pipermail/libc-alpha/2023-March/146219.html I explain: On a typical system, there are - hundreds of programs that call gettimeofday() or timespec_get(), - hundreds of programs that call time(). Each time a program calls gettimeofday() or timespec_get(), and then, within 1 to 3 milliseconds, a program (the same or a different one) calls time(), there is the potential for trouble because the time appears to go backwards. This trouble can occur with probability between 0.1% and 0.3%. This is the kind of trouble that does occur, but that people don't report because - it occurs only 1 in 300 to 1000 times, - it is nearly impossible to track down to glibc, since it will appear as an interoperation bug between two different programs in the first place. --=20 You are receiving this mail because: You are on the CC list for the bug.=