Re: [webmin-l] Confusing memory usage shown

[Chris <chr...@gm...>]

On Wed, 2018-08-29 at 16:23 -0700, Jamie Cameron wrote:
> On 28/Aug/2018 17:37 Chris <chr...@gm...> wrote ..
> > On Tue, 2018-08-28 at 15:02 -0700, Jamie Cameron wrote:
> > > On 28/Aug/2018 05:35 Chris <chr...@gm...> wrote ..
> > > > This is webmin 1.890 on a Ubuntu 18.04 system. I just upgraded
> > > > from
> > > > 4GB
> > > > to 16GB of ram yesterday. Top shows for memory installed and
> > > > usage:
> > > > 
> > > > KiB Mem :15354192 total,   567168 free,  3916928 used, 10870096
> > > > buff/cache
> > > > KiB Swap:  4089852 total,  4089852 free,       0 used. 11417092
> > > > avail
> > > > Mem
> > > > 
> > > > While webmin shows
> > > > 
> > > > Real memory 	7.11 GB used, 14.64 GB total
> > > > 
> > > > I'm just curious as to why there's such a difference in what
> > > > Top
> > > > shows
> > > > and what is shown on the webmin system information page.
> > > 
> > > Can you post the contents of /proc/meminfo on your system? That's
> > > the
> > > file
> > > Webmin reads to get memory usage.
> > > 
> > 
> > Sure:
> > 
> > cat meminfo
> > MemTotal:       15354192 kB
> > MemFree:          777936 kB
> > MemAvailable:   10696944 kB
> > Buffers:         2065336 kB
> > Cached:          4475436 kB
> > SwapCached:            0 kB
> > Active:          7384716 kB
> > Inactive:        3485364 kB
> > Active(anon):    3635112 kB
> > Inactive(anon):   426932 kB
> > Active(file):    3749604 kB
> > Inactive(file):  3058432 kB
> > Unevictable:         160 kB
> > Mlocked:             160 kB
> > SwapTotal:       4089852 kB
> > SwapFree:        4089852 kB
> > Dirty:               444 kB
> > Writeback:             0 kB
> > AnonPages:       4329492 kB
> > Mapped:           586328 kB
> > Shmem:            369504 kB
> > Slab:            3547476 kB
> > SReclaimable:    3445156 kB
> > SUnreclaim:       102320 kB
> > KernelStack:       14976 kB
> > PageTables:        76176 kB
> > NFS_Unstable:          0 kB
> > Bounce:                0 kB
> > WritebackTmp:          0 kB
> > CommitLimit:    11766948 kB
> > Committed_AS:   11178040 kB
> > VmallocTotal:   34359738367 kB
> > VmallocUsed:           0 kB
> > VmallocChunk:          0 kB
> > HardwareCorrupted:     0 kB
> > AnonHugePages:         0 kB
> > ShmemHugePages:        0 kB
> > ShmemPmdMapped:        0 kB
> > CmaTotal:              0 kB
> > CmaFree:               0 kB
> > HugePages_Total:       0
> > HugePages_Free:        0
> > HugePages_Rsvd:        0
> > HugePages_Surp:        0
> > Hugepagesize:       2048 kB
> > DirectMap4k:      356348 kB
> > DirectMap2M:    15333376 kB
> 
> So Webmin counts MemFree + Buffers + Cached
> as free, as the latter two are cached data
> that can be written back to disk, and thus
> available for allocation if needed.
>  
Thanks Jamie, appreciate the feedback. I understand now.

Chris

-- 
Chris
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