From nobody Sat Mar 25 18:58:55 2023 X-Original-To: freebsd-hackers@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4PkTCk6m0vz41b2k for ; Sat, 25 Mar 2023 19:09:38 +0000 (UTC) (envelope-from pmc@citylink.dinoex.sub.org) Received: from uucp.dinoex.org (uucp.dinoex.org [IPv6:2a0b:f840::12]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "uucp.dinoex.sub.de", Issuer "R3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4PkTCk2PBdz3Nhh for ; Sat, 25 Mar 2023 19:09:38 +0000 (UTC) (envelope-from pmc@citylink.dinoex.sub.org) Authentication-Results: mx1.freebsd.org; none Received: from uucp.dinoex.org (uucp.dinoex.org [IPv6:2a0b:f840:0:0:0:0:0:12]) by uucp.dinoex.org (8.17.1/8.17.1) with ESMTPS id 32PJ97Bu097145 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NO); Sat, 25 Mar 2023 20:09:07 +0100 (CET) (envelope-from pmc@citylink.dinoex.sub.org) Received: (from uucp@localhost) by uucp.dinoex.org (8.17.1/8.17.1/Submit) with UUCP id 32PJ97Uc097144; Sat, 25 Mar 2023 20:09:07 +0100 (CET) (envelope-from pmc@citylink.dinoex.sub.org) Received: from disp.intra.daemon.contact (disp-e.intra.daemon.contact [IPv6:fd00:0:0:0:0:0:0:112]) by admn.intra.daemon.contact (8.17.1/8.17.1) with ESMTPS id 32PJ1cCF077148 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=OK); Sat, 25 Mar 2023 20:01:39 +0100 (CET) (envelope-from pmc@citylink.dinoex.sub.org) Received: from disp.intra.daemon.contact (localhost [127.0.0.1]) by disp.intra.daemon.contact (8.17.1/8.17.1) with ESMTPS id 32PIwtBB006163 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NO); Sat, 25 Mar 2023 19:58:55 +0100 (CET) (envelope-from pmc@citylink.dinoex.sub.org) Received: (from pmc@localhost) by disp.intra.daemon.contact (8.17.1/8.17.1/Submit) id 32PIwt3j006162; Sat, 25 Mar 2023 19:58:55 +0100 (CET) (envelope-from pmc@citylink.dinoex.sub.org) X-Authentication-Warning: disp.intra.daemon.contact: pmc set sender to pmc@citylink.dinoex.sub.org using -f Date: Sat, 25 Mar 2023 19:58:55 +0100 From: Peter To: Mark Millard Cc: FreeBSD Hackers Subject: Re: Periodic rant about SCHED_ULE Message-ID: References: <5AF26266-5B4C-4A7F-8784-4C6308B6C5CA.ref@yahoo.com> <5AF26266-5B4C-4A7F-8784-4C6308B6C5CA@yahoo.com> List-Id: Technical discussions relating to FreeBSD List-Archive: https://lists.freebsd.org/archives/freebsd-hackers List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-hackers@freebsd.org MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5AF26266-5B4C-4A7F-8784-4C6308B6C5CA@yahoo.com> X-Milter: Spamilter (Reciever: uucp.dinoex.org; Sender-ip: 0:0:2a0b:f840::; Sender-helo: uucp.dinoex.org;) X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (uucp.dinoex.org [IPv6:2a0b:f840:0:0:0:0:0:12]); Sat, 25 Mar 2023 20:09:09 +0100 (CET) X-Rspamd-Queue-Id: 4PkTCk2PBdz3Nhh X-Spamd-Bar: ---- X-Spamd-Result: default: False [-4.00 / 15.00]; REPLY(-4.00)[]; ASN(0.00)[asn:205376, ipnet:2a0b:f840::/32, country:DE] X-Rspamd-Pre-Result: action=no action; module=replies; Message is reply to one we originated X-ThisMailContainsUnwantedMimeParts: N On Sat, Mar 25, 2023 at 11:14:11AM -0700, Mark Millard wrote: ! Why did PID 10675 change to 19028? Because it went into some NFS share, and it would still be there if I hadn't restartet it a bit differently. ! When I tried that tar line, I get lots of output to stderr: ! ! # tar cvf - / | cpuset -l 13 gzip -9 > /dev/null ! tar: Removing leading '/' from member names ! a . ! a root ! a wrkdirs ! a bin ! a usr ! . . . ! ! Was that an intentional part of the test? Yes. So you can see what it is currently feeding to gzip (small or big files - or some NFS share, where the operation becomes pointless). ! # tar cvf - / 2>/dev/null | cpuset -l 13 gzip -9 2>&1 > /dev/null ! ! At which point I get the likes of: ! ! 17129 root 1 68 0 14192Ki 3628Ki RUN 13 0:20 3.95% gzip -9 ! 17128 root 1 20 0 58300Ki 13880Ki pipdwt 18 0:00 0.27% tar cvf - / (bsdtar) ! 17097 root 1 133 0 13364Ki 3060Ki CPU13 13 8:05 95.93% sh -c while true; do :; done ! ! up front. Ah. So? To me this doesn't look good. If both jobs are runnable, they should each get ~50%. ! For reference, I also see the likes of the following from ! "gstat -spod" (it is a root on ZFS context with PCIe Optane media): So we might assume that indeed both jobs are runable, and the only significant difference is that one does system calls while the other doesn't. The point of this all is: identify the malfunction with the most simple usecase. (And for me here is a malfunction.) And then, obviousely, fix it.