XOA memory consumption.

[Tristis Oris]

Greetings.
not a problem, just to know.

1. How much memory XOA really required
2. and any point to increase resources?
3. Or it will consume any available memory without any visible profit.

We have ~140 VM, 10 pools, backup tasks, etc.
During backups XOA eat all available memory. It was 8Gb, then 16, now 60.
last tests here, just a few VMs backups ~50-150gb total.

[olivierlambert]

Question for @julien-f

[julien-f]

@tristis-oris XO consists of multiple processes (main xo-server, backup workers and merge worker), can you please check and tell me which process(es) are eating the memory?

[Tristis Oris]

@julien-f
first 10min usage was ~4Gb, then slowly grow.

free -m
              total        used        free      shared  buff/cache   available
Mem:          64405         889       18383           1       45132       62827
Swap:          3912           2        3910

cat /proc/meminfo
MemTotal:       65951364 kB
MemFree:        19057564 kB
MemAvailable:   64344288 kB
Buffers:           73420 kB
Cached:         45693660 kB
SwapCached:           20 kB
Active:           432944 kB
Inactive:       45829948 kB
Active(anon):     248744 kB
Inactive(anon):   248388 kB
Active(file):     184200 kB
Inactive(file): 45581560 kB
Unevictable:           0 kB
Mlocked:               0 kB
SwapTotal:       4006908 kB
SwapFree:        4004092 kB
Dirty:           1248900 kB
Writeback:             0 kB
AnonPages:        496172 kB
Mapped:            92384 kB
Shmem:              1040 kB
Slab:             427740 kB
SReclaimable:     223828 kB
SUnreclaim:       203912 kB
KernelStack:        6464 kB
PageTables:        10196 kB
NFS_Unstable:          0 kB
Bounce:                0 kB
WritebackTmp:          0 kB
CommitLimit:    36982588 kB
Committed_AS:     959248 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:      468992 kB
DirectMap2M:    28882944 kB
DirectMap1G:    38797312 kB


vmstat -s
     65951364 K total memory
       903496 K used memory
       433108 K active memory
     45665008 K inactive memory
     19221716 K free memory
        73420 K buffer memory
     45752732 K swap cache
      4006908 K total swap
         2816 K used swap
      4004092 K free swap
      1722699 non-nice user cpu ticks
          927 nice user cpu ticks
       650973 system cpu ticks
     93226562 idle cpu ticks
       562428 IO-wait cpu ticks
            0 IRQ cpu ticks
        88662 softirq cpu ticks
       199013 stolen cpu ticks
      1744586 pages paged in
       651916 pages paged out
            8 pages swapped in
           56 pages swapped out
    659058082 interrupts
    531357650 CPU context switches
   1637953158 boot time
        16715 forks

[ronivay]

Looking at the cli output this sounds like a classic confusion of how memory is used in linux. As you can see from free command output, you actually have majority of the memory still available. Graph in XO doesn’t tell much how the memory is actually being used so it might be confusing as most of it is in cache and buffers which usually is something that can be released into use immediately if an application needs ram.

I suggest reading for example this to understand more: https://www.linuxatemyram.com/

[Tristis Oris]

@ronivay yes i see, most "used" memory just a cached. so as i ask before

1. How much memory XOA really required
2. and any point to increase resources?
3. Or it will consume any available memory without any visible profit.

is it fine to have 4gb for any installation size?

[ronivay]

@tristis-oris i don’t have a definitive answer what would be the perfect memory configuration for your needs. I commented based on your earlier findings that VM memory usage was high which doesn’t take into account what OS inside VM is doing with the memory. As you observed, most of the memory is used by cache so it basically has nothing to do with XO, just how Linux manages the usable memory.