In message <20160402113910.14de7eaf.ohartman_at_zedat.fu-berlin.de>, "O. Hartmann" writes: > --Sig_/cnPyYwlIcD24/.m6dd2EX7j > Content-Type: text/plain; charset=US-ASCII > Content-Transfer-Encoding: quoted-printable > > Am Sat, 2 Apr 2016 10:55:03 +0200 > "O. Hartmann" <ohartman_at_zedat.fu-berlin.de> schrieb: > > > Am Sat, 02 Apr 2016 01:07:55 -0700 > > Cy Schubert <Cy.Schubert_at_komquats.com> schrieb: > >=20 > > > In message <56F6C6B0.6010103_at_protected-networks.net>, Michael Butler wr= > ites: =20 > > > > -current is not great for interactive use at all. The strategy of > > > > pre-emptively dropping idle processes to swap is hurting .. big time.= > =20 > > >=20 > > > FreeBSD doesn't "preemptively" or arbitrarily push pages out to disk. L= > RU=20 > > > doesn't do this. > > > =20 > > > >=20 > > > > Compare inactive memory to swap in this example .. > > > >=20 > > > > 110 processes: 1 running, 108 sleeping, 1 zombie > > > > CPU: 1.2% user, 0.0% nice, 4.3% system, 0.0% interrupt, 94.5% idle > > > > Mem: 474M Active, 1609M Inact, 764M Wired, 281M Buf, 119M Free > > > > Swap: 4096M Total, 917M Used, 3178M Free, 22% Inuse =20 > > >=20 > > > To analyze this you need to capture vmstat output. You'll see the free = > pool=20 > > > dip below a threshold and pages go out to disk in response. If you have= > =20 > > > daemons with small working sets, pages that are not part of the working= > =20 > > > sets for daemons or applications will eventually be paged out. This is = > not=20 > > > a bad thing. In your example above, the 281 MB of UFS buffers are more= > =20 > > > active than the 917 MB paged out. If it's paged out and never used agai= > n,=20 > > > then it doesn't hurt. However the 281 MB of buffers saves you I/O. The= > =20 > > > inactive pages are part of your free pool that were active at one time = > but=20 > > > now are not. They may be reclaimed and if they are, you've just saved m= > ore=20 > > > I/O. > > >=20 > > > Top is a poor tool to analyze memory use. Vmstat is the better tool to = > help=20 > > > understand memory use. Inactive memory isn't a bad thing per se. Monito= > r=20 > > > page outs, scan rate and page reclaims. > > >=20 > > > =20 > >=20 > > I give up! Tried to check via ssh/vmstat what is going on. Last lines bef= > ore broken > > pipe: > >=20 > > [...] > > procs memory page disks faults cpu > > r b w avm fre flt re pi po fr sr ad0 ad1 in sy cs us= > sy id > > 22 0 22 5.8G 1.0G 46319 0 0 0 55721 1297 0 4 219 23907 5400 = > 95 5 0 > > 22 0 22 5.4G 1.3G 51733 0 0 0 72436 1162 0 0 108 40869 3459 = > 93 7 0 > > 15 0 22 12G 1.2G 54400 0 27 0 52188 1160 0 42 148 52192 4366 = > 91 9 0 > > 14 0 22 12G 1.0G 44954 0 37 0 37550 1179 0 39 141 86209 4368 = > 88 12 0 > > 26 0 22 12G 1.1G 60258 0 81 0 69459 1119 0 27 123 779569 70435= > 9 87 13 0 > > 29 3 22 13G 774M 50576 0 68 0 32204 1304 0 2 102 507337 48486= > 1 93 7 0 > > 27 0 22 13G 937M 47477 0 48 0 59458 1264 3 2 112 68131 44407 = > 95 5 0 > > 36 0 22 13G 829M 83164 0 2 0 82575 1225 1 0 126 99366 38060 = > 89 11 0 > > 35 0 22 6.2G 1.1G 98803 0 13 0 121375 1217 2 8 112 99371 4999= > 85 15 0 > > 34 0 22 13G 723M 54436 0 20 0 36952 1276 0 17 153 29142 4431 = > 95 5 0 > > Fssh_packet_write_wait: Connection to 192.168.0.1 port 22: Broken pipe > >=20 > >=20 > > This makes this crap system completely unusable. The server (FreeBSD 11.0= > -CURRENT #20 > > r297503: Sat Apr 2 09:02:41 CEST 2016 amd64) in question did poudriere b= > ulk job. I can > > not even determine what terminal goes down first - another one, much more= > time idle than > > the one shwoing the "vmstat 5" output, is still alive!=20 > >=20 > > i consider this a serious bug and it is no benefit what happened since th= > is "fancy" > > update. :-( > > By the way - it might be of interest and some hint. > > One of my boxes is acting as server and gateway. It utilises NAT, IPFW, whe= > n it is under > high load, as it was today, sometimes passing the network flow from ISP int= > o the network > for clients is extremely slow. I do not consider this the reason for collap= > sing ssh > sessions, since this incident happens also under no-load, but in the overal= > l-view onto > the problem, this could be a hint - I hope.=20 Natd is a critical part of your network infrastructure. rtprio 1 natd or rtprio 1 it after the fact. It won't hurt and it'll take this variable out of consideration, as much as we can. -- Cheers, Cy Schubert <Cy.Schubert_at_komquats.com> or <Cy.Schubert_at_cschubert.com> FreeBSD UNIX: <cy_at_FreeBSD.org> Web: http://www.FreeBSD.org The need of the many outweighs the greed of the few.Received on Sat Apr 02 2016 - 21:33:08 UTC
This archive was generated by hypermail 2.4.0 : Wed May 19 2021 - 11:41:03 UTC