→ Applies to: SynetoOS 6.x and above

Symptom

Error “Operating system storage space usage has exceeded 80% threshold. Consider freeing up space or expanding storage capacity to maintain optimal performance.” appears due to swap files consuming excessive space.

Solution

Step 1. Connect to SynetoOS appliance via SSH as admin

ssh admin@<your_ip_address_or_hostname>

Step 2. Get root privileges

sudo su -

Step 3. Check disk usage on the root partition

df -h /

EXAMPLE OUTPUT

Filesystem      Size  Used Avail Use% Mounted on
/dev/md126      196G  155G   41G  80% /

Step 4. Identify which directory is consuming the space

du -sch /var/lib/* | grep G

EXAMPLE OUTPUT

9.8G    /var/lib/containerd
7.9G    /var/lib/rsyslog
120G    /var/lib/swap
140G    total

NOTE
In this example, /var/lib/swap accounts for the majority of disk usage.

Step 5. List the swap files

ls -halt /var/lib/swap

EXAMPLE OUTPUT

total 121G
-rw-------   1 root root 8.0G Jul 15 13:54 swapfile_14
drwxr-xr-x   2 root root  281 Jul 15 13:54 .
-rw-------   1 root root 8.0G Jul 15 13:54 swapfile_13
-rw-------   1 root root 8.0G Jul 15 13:54 swapfile_12
-rw-------   1 root root 8.0G Jul 15 13:54 swapfile_11
-rw-------   1 root root 8.0G Jul 15 13:54 swapfile_10
-rw-------   1 root root 8.0G Jul 15 13:54 swapfile_9
-rw-------   1 root root 8.0G Jul 15 12:54 swapfile_8
-rw-------   1 root root 8.0G Jul 15 12:54 swapfile_7
-rw-------   1 root root 8.0G Jul 15 12:54 swapfile_6
-rw-------   1 root root 8.0G Jul 15 12:54 swapfile_5
-rw-------   1 root root 8.0G Jul 15 12:54 swapfile_4
-rw-------   1 root root 8.0G Jul 15 12:54 swapfile_3
-rw-------   1 root root 8.0G Jul 15 12:54 swapfile_2
-rw-------   1 root root 8.0G Jul 15 12:54 swapfile_1
-rw-------   1 root root 8.0G Jul 15 12:54 swapfile_0
drwxr-xr-x. 65 root root 4.0K Jun 17 10:03 ..

Step 6. Check the system's memory allocation configuration

syneto-memory-info

EXAMPLE OUTPUT

[root@syneto-os6-02 ~]# syneto-memory-info 
============================================================
CURRENT SYSTEM MEMORY ALLOCATION DECISIONS
============================================================

📊 SYSTEM RESOURCES:
  Total RAM:                 250 GB
  Available Disk:            40 GB (raw)
  Effective Available Disk:  160 GB (including existing swap)

🧮 MEMORY BREAKDOWN:
  OS Reserved:                12 GB
  ARC Cache:                  50 GB
  Usable RAM for VMs:         188 GB

💾 RECOMMENDED SWAP CONFIGURATION:
  zRAM Size:                  15 GB
  Disk Swap Chunks:           15 × 8 GB
  Total Disk Swap:           120 GB
  Total Swap:                135 GB

📋 ACTIVE SWAP CONFIGURATION:
  zRAM Size:                  4 GB
  Disk Swap Chunks:           15 × 8 GB
  Total Disk Swap:           120 GB
  Total Swap:                124 GB

🖥️  VIRTUAL MACHINE CAPACITY:
  Max VM Memory:             323 GB
  Memory Efficiency:   1.3x RAM

📈 SWAP UTILIZATION:
  Disk Utilization:       100.0% of available
  Swap/RAM Ratio:      0.5:1

⚙️  CURRENT ARC SETTING:
  Current ARC Max:           50 GB
  Recommended ARC:            50 GB

IMPORTANT
The system's disk swap allocation is configured too high relative to available disk space. 
In this example, disk swap utilization is at 100% of available space.

Step 7. Copy the Syneto Diana service configuration template

cp /etc/syneto-diana-memory-sizer.yaml.default /etc/syneto-diana-memory-sizer.yaml

Step 8. Edit the configuration file

vi /etc/syneto-diana-memory-sizer.yaml

IMPORTANT
Make sure to copy and paste the exact lines below.

# Swap Configuration
swap:
  # Percentage of available disk space to use for swap (default: 75%)
  disk_usage_percentage: 0.50

Save and Exit

:wq

NOTE
The default value is 75% of available disk space. Lower it to 50%.

Step 9. Restart the Syneto Diana service

systemctl restart syneto-diana.service

Step 10. Check disk usage

df -h /

EXAMPLE OUTPUT

Filesystem      Size  Used Avail Use% Mounted on
/dev/md126      196G  115G   81G  59% /

Step 11. Check the memory allocation configuration

syneto-memory-info

EXAMPLE OUTPUT

[root@syneto-os6-02 swap]# syneto-memory-info 
============================================================
CURRENT SYSTEM MEMORY ALLOCATION DECISIONS
============================================================

📊 SYSTEM RESOURCES:
  Total RAM:                 250 GB
  Available Disk:            80 GB (raw)
  Effective Available Disk:  160 GB (including existing swap)

🧮 MEMORY BREAKDOWN:
  OS Reserved:                12 GB
  ARC Cache:                  50 GB
  Usable RAM for VMs:         188 GB

💾 RECOMMENDED SWAP CONFIGURATION:
  zRAM Size:                  15 GB
  Disk Swap Chunks:           5 × 16 GB
  Total Disk Swap:           80 GB
  Total Swap:                95 GB

📋 ACTIVE SWAP CONFIGURATION:
  zRAM Size:                  4 GB
  Disk Swap Chunks:           0 × 0 GB
  Total Disk Swap:           0 GB
  Total Swap:                4 GB

🖥️  VIRTUAL MACHINE CAPACITY:
  Max VM Memory:             283 GB
  Memory Efficiency:   1.1x RAM

📈 SWAP UTILIZATION:
  Disk Utilization:       66.7% of available
  Swap/RAM Ratio:      0.4:1

⚙️  CURRENT ARC SETTING:
  Current ARC Max:           50 GB
  Recommended ARC:            50 GB

Step 12. Confirm the swap files were reduced

ls -halt /var/lib/swap/

EXAMPLE OUTPUT

total 81G
-rw-------   1 root root  16G Jul 24 09:08 swapfile_4
drwxr-xr-x   2 root root   96 Jul 24 09:08 .
-rw-------   1 root root  16G Jul 24 09:08 swapfile_3
-rw-------   1 root root  16G Jul 24 09:08 swapfile_2
-rw-------   1 root root  16G Jul 24 09:08 swapfile_1
-rw-------   1 root root  16G Jul 24 09:08 swapfile_0
drwxr-xr-x. 65 root root 4.0K Jun 17 10:03 ..