Hi Matthew, thanks for your answer. so, when this tools say that the memused is 3,4G this is true but with the detail that the amount allocated in buffers y cache are avaliable to use, isnt it? one finally doubt is about swap, Why I have an 8% of swap if I really have a lot of free mem? Well, with this I think I can tell my boss that we don´t need to buy more mem ;-) Greetings, ESG 2010/3/17 Stainforth, Matthew (SD/DS) <Matthew.Stainforth@xxxxxx> > Is is fine. The output of sar, free, top, and vmstat are all agreeing that > you have about 3.4GB mem used (~82%) with about 750MB free. > > The kbbuffers and kbcached from sar agrees with buffers (.48 GB) and cached > (.56 GB) from free. The buff and cached from vmstat also agrees. > > Now if you look at the -/+ buffers/cache line from free, you will see that > you really only have 2.36GB used and 1.78GB free if you don't count buffers > and cache. 2.36GB + .48GB + .56GB = 3.4GB used. > > So you have about a gig of memory tied up in buffers and cache that could > be freed if needed by the system. > > Further, you only have 40MB (8%) of swap used. If you were starved for > memory this would be higher and your cache and buffers would be lower. > > > -----Original Message----- > > From: redhat-list-bounces@xxxxxxxxxx [mailto:redhat-list- > > bounces@xxxxxxxxxx] On Behalf Of ESGLinux > > Sent: Wednesday, March 17, 2010 5:44 AM > > To: General Red Hat Linux discussion list > > Subject: confused with memory usage, sar, top, free, vmstat > > > > Hi all, > > > > I have a server that I think is having problems with memory usage but > > when I > > try to analize with different tools I´m not sure if I having problems > > with > > it > > > > If I run sar -r: > > ... > > 04:50:01 kbmemfree kbmemused %memused kbbuffers kbcached kbswpfree > > kbswpused %swpused kbswpcad > > 09:05:01 748036 3401232 81,97 448672 599232 > > 3768868 327664 8,00 40456 > > 09:10:01 749596 3399672 81,93 480028 560856 > > 3768868 327664 8,00 40456 > > 09:15:01 749020 3400248 81,95 481144 559740 > > 3768868 327664 8,00 40456 > > 09:20:01 749516 3399752 81,94 481812 559332 > > 3768868 327664 8,00 40456 > > 09:25:01 749676 3399592 81,93 481928 559216 > > 3768868 327664 8,00 40456 > > ... > > > > free > > total used free shared > > buffers cached > > Mem: 4149268 3407624 741644 0 481084 > > 566300 > > -/+ buffers/cache: 2360240 1789028 > > Swap: 4096532 327664 3768868 > > > > vmstat 1 > > procs -----------memory---------- ---swap-- -----io---- --system-- > > ----cpu---- > > r b swpd free buff cache si so bi bo in cs us > > sy id > > wa > > 0 0 327664 741412 481444 566200 1 1 10 56 0 2 2 > > 1 96 > > 1 > > 0 0 327664 741412 481452 566192 0 0 0 24 1017 880 1 > > 0 99 > > 1 > > 0 0 327664 741428 481460 566184 0 0 0 60 1012 812 0 > > 0 99 > > 1 > > 0 0 327664 741428 481460 566184 0 0 0 0 1008 835 0 > > 0 100 > > 0 > > 2 1 327664 741428 481464 566180 0 0 0 12 1020 859 0 > > 0 100 > > 0 > > > > top -b -d 1 -n 1 > > top - 09:37:02 up 141 days, 20:15, 1 user, load average: 0.00, 0.02, > > 0.03 > > Tasks: 115 total, 1 running, 114 sleeping, 0 stopped, 0 zombie > > Cpu(s): 1.6% us, 0.6% sy, 0.2% ni, 96.4% id, 1.2% wa, 0.0% hi, > > 0.0% si > > Mem: 4149268k total, 3408280k used, 740988k free, 481752k > > buffers > > Swap: 4096532k total, 327664k used, 3768868k free, 566152k cached > > > > I have read that linux try to allocate all the RAM memory, so the real > > free > > memory is the free + buffers/cache, is it true? if so, the %memused > > shown by > > sar -r is not true? > > > > Can anybody give a light to understand this (docs, tools...)? with the > > commands I have post do you think that I´m having problems with the > > memory > > or can I be calm? > > > > Thanks in advance > > > > ESG > > -- > > redhat-list mailing list > > unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe > > https://www.redhat.com/mailman/listinfo/redhat-list > > -- > redhat-list mailing list > unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe > https://www.redhat.com/mailman/listinfo/redhat-list > -- redhat-list mailing list unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe https://www.redhat.com/mailman/listinfo/redhat-list
