calc.engineer / Homelab & Networking / ZFS Ram

ZFS Ram v1.0.0

Calculate recommended RAM and ARC sizing for a ZFS storage pool based on workload type, pool size, deduplication status, and L2ARC cache size. Computes minimum and recommended RAM in gigabytes, ARC target size, and dedup table overhead. Accounts for workload-specific IO patterns: NAS (sequential, 1GB/TB), database (random, 2GB/TB), virtualization (mixed, 1.5GB/TB). Deduplication adds approximately 5GB per TB for the DDT. L2ARC index requires 1GB RAM per 10GB of L2ARC. Essential for TrueNAS, FreeNAS, and custom ZFS server builds.

← from zfs_capacity
Total usable pool size in terabytes
Primary workload type: general (mixed), nas (sequential reads/writes), database (random IO), virtualization (mixed random)
Size of L2ARC (read cache SSD) in gigabytes; requires additional RAM for index
Fill in the inputs and Compute to see the structured result.

From an agent (MCP) or the API

curl -X POST https://calc.engineer/api/zfs_ram \
  -H "Content-Type: application/json" \
  -d '{"pool_size_tb": …, "workload": …, "dedup_enabled": …}'

MCP: connect to https://calc.engineer/mcp and call zfs_ram.

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