webadmin-list

[webmin-l] Confusing memory usage shown

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

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.

-- 
Chris
31.11972; -97.90167 (Elev. 1092 ft)
07:31:32 up 15:46, 1 user, load average: 1.08, 0.68, 0.56
Description:	Ubuntu 18.04.1 LTS, kernel 4.15.0-33-generic

Re: [webmin-l] Confusing memory usage shown

[Jamie C. <jca...@we...>]

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.

Re: [webmin-l] Confusing memory usage shown

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

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

I sent this then forgot that I had to unsubscribe my @embarqmail.com
address due to this

A message that you sent could not be delivered to one or more of its
recipients. This is a permanent error. The following address(es)
failed:

>>> web...@li... (after RCPT TO): 550-Message
rejected. Your IP (206.152.134.66) has been flagged for sending
550-SPAM by the UCE Protect Level 1 blocklist. For more information,
see
550 http://www.uceprotect.net/en/rblcheck.php .

-- 
Chris
31.11972; -97.90167 (Elev. 1092 ft)
19:34:44 up 1 day, 3:49, 2 users, load average: 0.83, 0.50, 0.26
Description:	Ubuntu 18.04.1 LTS, kernel 4.15.0-33-generic

Re: [webmin-l] Confusing memory usage shown

[Jamie C. <jca...@we...>]

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.
 

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
KeyID 0xE372A7DA98E6705C
31.11972; -97.90167 (Elev. 1092 ft)
20:21:29 up 2 days, 4:36, 2 users, load average: 0.96, 0.96, 0.88
Description:	Ubuntu 18.04.1 LTS, kernel 4.15.0-33-generic