From owner-freebsd-stable@FreeBSD.ORG Thu Jan 27 00:59:29 2011 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id A121E106564A for ; Thu, 27 Jan 2011 00:59:29 +0000 (UTC) (envelope-from bartosz.stec@it4pro.pl) Received: from mainframe.kkip.pl (kkip.pl [87.105.164.78]) by mx1.freebsd.org (Postfix) with ESMTP id 080208FC08 for ; Thu, 27 Jan 2011 00:59:28 +0000 (UTC) Received: from static-78-8-144-74.ssp.dialog.net.pl ([78.8.144.74] helo=[192.168.0.2]) by mainframe.kkip.pl with esmtpsa (TLSv1:CAMELLIA256-SHA:256) (Exim 4.73 (FreeBSD)) (envelope-from ) id 1PiGCi-0009jj-Ah for freebsd-stable@freebsd.org; Thu, 27 Jan 2011 01:59:27 +0100 Message-ID: <4D40C355.6070306@it4pro.pl> Date: Thu, 27 Jan 2011 01:59:01 +0100 From: Bartosz Stec Organization: IT4Pro User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; pl; rv:1.9.2.13) Gecko/20101207 Lightning/1.0b2 Thunderbird/3.1.7 MIME-Version: 1.0 To: freebsd-stable@freebsd.org References: <4D401192.3030400@it4pro.pl> <201101261235.56856.jhb@freebsd.org> <20110126180402.GA17271@tolstoy.tols.org> <201101261344.50756.jhb@freebsd.org> In-Reply-To: <201101261344.50756.jhb@freebsd.org> X-Authenticated-User: bartosz.stec@it4pro.pl X-Authenticator: plain X-Sender-Verify: SUCCEEDED (sender exists & accepts mail) X-Spam-Score: -8.1 X-Spam-Score-Int: -80 X-Exim-Version: 4.73 (build at 10-Jan-2011 16:29:01) X-Date: 2011-01-27 01:59:27 X-Connected-IP: 78.8.144.74:64347 X-Message-Linecount: 353 X-Body-Linecount: 340 X-Message-Size: 13242 X-Body-Size: 12582 X-Received-Count: 1 X-Recipient-Count: 1 X-Local-Recipient-Count: 1 X-Local-Recipient-Defer-Count: 0 X-Local-Recipient-Fail-Count: 0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Subject: Re: top shows only part of available physmem X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 27 Jan 2011 00:59:29 -0000 W dniu 2011-01-26 19:44, John Baldwin pisze: > On Wednesday, January 26, 2011 1:04:02 pm Marco van Tol wrote: >> On Wed, Jan 26, 2011 at 12:35:56PM -0500, John Baldwin wrote: >>> On Wednesday, January 26, 2011 8:20:28 am Bartosz Stec wrote: >>>> W dniu 2011-01-26 14:06, John Baldwin pisze: >>>>> On Wednesday, January 26, 2011 7:20:34 am Bartosz Stec wrote: >>>>>> Guys, >>>>>> >>>>>> could someone explain me this? >>>>>> >>>>>> # sysctl hw.realmem >>>>>> hw.realmem: 2139029504 >>>>>> >>>>>> top line shows: >>>>>> >>>>>> Mem: 32M Active, 35M Inact, 899M Wired, 8392K Cache, 199M Buf, 58M Free >>>>>> >>>>>> 32+35+899+8+199+58 = 1231MB >>>>>> >>>>>> Shouldn't that sum to all available ram? Or maybe I'm reading it wrong? >>>>>> This machine has indeed 2GB of ram on board and showed in BIOS. >>>>>> i386 FreeBSD 8.2-PRERELEASE #16: Mon Jan 17 22:28:53 CET 2011 >>>>>> Cheers. >>>>> First, don't include 'buf' as isn't a separate set of RAM, it is only a range >>>>> of the virtual address space in the kernel. It used to be relevant when the >>>>> buffer cache was separate from the VM page cache, but now it is mostly >>>>> irrelevant (arguably it should just be dropped from top output). >>>> Thanks for the explanation. So 1231MB - 199MB Buf and we got about 1GB >>>> of memory instead of 2B. >>>> >>>>> However, look at what hw.physmem says (and the realmem and availmem lines in >>>>> dmesg). realmem is actually not that useful as it is not a count of the >>>>> amount of memory, but the address of the highest memory page available. There >>>>> can be less memory available than that due to "holes" in the address space for >>>>> PCI memory BARs, etc. >>>>> >>>> OK, here you go: >>>> # sysctl hw | grep mem >>>> >>>> hw.physmem: 2125893632 >>>> hw.usermem: 1212100608 >>>> hw.realmem: 2139029504 >>>> hw.pci.host_mem_start: 2147483648 >>> Humm, you should still have 2GB of RAM then. All the memory you set aside >>> for ARC should be counted in the 'wired' count, so I'm not sure why you see >>> 1GB of RAM rather than 2GB. >> For what its worth (seems to be the same values top shows), the sysctl's >> I use to make cacti graphs of memory usage are: (Counts are in pages) >> >> vm.stats.vm.v_page_size >> >> vm.stats.vm.v_wire_count >> vm.stats.vm.v_active_count >> vm.stats.vm.v_inactive_count >> vm.stats.vm.v_cache_count >> vm.stats.vm.v_free_count >> >> Using the output of those sysctls I allways get a cacti graph which at >> least very much seems to account for all memory, and has a flat surface >> in a stacked graph. > These sysctls are exactly what top uses. There is also a 'v_page_count' > which is a total count of pages. > So here's additional sysctl output from now: fbsd# sysctl hw | grep mem hw.physmem: 2125893632 hw.usermem: 1392594944 hw.realmem: 2139029504 hw.pci.host_mem_start: 2147483648 fbsd# sysctl vm.stats.vm vm.stats.vm.v_kthreadpages: 0 vm.stats.vm.v_rforkpages: 0 vm.stats.vm.v_vforkpages: 1422927 vm.stats.vm.v_forkpages: 4606557 vm.stats.vm.v_kthreads: 40 vm.stats.vm.v_rforks: 0 vm.stats.vm.v_vforks: 9917 vm.stats.vm.v_forks: 30429 vm.stats.vm.v_interrupt_free_min: 2 vm.stats.vm.v_pageout_free_min: 34 vm.stats.vm.v_cache_max: 27506 vm.stats.vm.v_cache_min: 13753 vm.stats.vm.v_cache_count: 20312 vm.stats.vm.v_inactive_count: 18591 vm.stats.vm.v_inactive_target: 20629 vm.stats.vm.v_active_count: 1096 vm.stats.vm.v_wire_count: 179027 vm.stats.vm.v_free_count: 6193 vm.stats.vm.v_free_min: 3260 vm.stats.vm.v_free_target: 13753 vm.stats.vm.v_free_reserved: 713 vm.stats.vm.v_page_count: 509752 vm.stats.vm.v_page_size: 4096 vm.stats.vm.v_tfree: 196418851 vm.stats.vm.v_pfree: 2837177 vm.stats.vm.v_dfree: 0 vm.stats.vm.v_tcached: 1305893 vm.stats.vm.v_pdpages: 3527455 vm.stats.vm.v_pdwakeups: 187 vm.stats.vm.v_reactivated: 83786 vm.stats.vm.v_intrans: 3053 vm.stats.vm.v_vnodepgsout: 134384 vm.stats.vm.v_vnodepgsin: 29213 vm.stats.vm.v_vnodeout: 96249 vm.stats.vm.v_vnodein: 29213 vm.stats.vm.v_swappgsout: 19730 vm.stats.vm.v_swappgsin: 8573 vm.stats.vm.v_swapout: 5287 vm.stats.vm.v_swapin: 2975 vm.stats.vm.v_ozfod: 83338 vm.stats.vm.v_zfod: 2462557 vm.stats.vm.v_cow_optim: 330 vm.stats.vm.v_cow_faults: 1239253 vm.stats.vm.v_vm_faults: 5898471 fbsd# sysctl vm.vmtotal vm.vmtotal: System wide totals computed every five seconds: (values in kilobytes) =============================================== Processes: (RUNQ: 1 Disk Wait: 0 Page Wait: 0 Sleep: 60) Virtual Memory: (Total: 4971660K Active: 699312K) Real Memory: (Total: 540776K Active: 29756K) Shared Virtual Memory: (Total: 41148K Active: 19468K) Shared Real Memory: (Total: 4964K Active: 3048K) Free Memory Pages: 105308K /usr/bin/top line: Mem: 4664K Active, 73M Inact, 700M Wired, 79M Cache, 199M Buf, 23M Free Sum (Without Buf): 879,5 MB So what are we looking at? Wrong sysctls/top output or maybe actually FreeBSD doesn't use all available RAM for some reason? Could it be hardware problem? Maybe I should provide some additional data? -- Bartosz Stec