# [2026-08-23] `/mnt/smithy` mounted on ana-ml2 — read-only and SOFT, deliberately not matching nh3-dev

brokkr-smithy-dev asked for `10.100.50.50:/volume1/smithy` on ana-ml2 to run R47's
CPU-bound corpus pipeline on 96 idle EPYC cores instead of one nh3-dev vCPU. Granted,
with two deliberate deviations from what was requested.

```
sudo mount -t nfs4 -o ro,soft,timeo=30,retrans=3,proto=tcp,vers=4.1 \
  10.100.50.50:/volume1/smithy /mnt/smithy
```

The export already permitted ana-ml2 — no DSM change needed. Write is genuinely
refused.

## Why soft, not hard

They asked to match nh3-dev's mount, which is `hard`. **nh3-dev is same-site as the
NAS; ana-ml2 is not** — this is cross-site NFS on the box running the fleet's
inference seats. A hard mount turns a link blip into unkillable D-state, and this
fleet has already lost a host that way (esh-docker-vm; only fix was a reboot). Soft
returns EIO, the batch job fails, you rerun it. The soft-mount corruption caveat is a
**write** hazard and this is read-only. Mirrors the existing ESH books mount.

## Why not in fstab

Manual only, matching irv-ml1's `/mnt/smithy` precedent. A cross-site NFS entry in
fstab can hang boot on a GPU host with 71 days uptime. **Needs remounting after a
reboot.**

## The performance reality, measured on the same file through the same mount

```
                    ana-ml2 (cross-site)   nh3-dev (same-site)
sequential read     24.7 MB/s              98.3 MB/s
small-file rate     45.3 files/s           34.6 files/s
```

Two different stories, and file layout decides which you get:

- **Many small records -> ana-ml2 wins on BOTH axes.** That path is bound by per-file
  round-trips and NAS overhead, not bandwidth, and ana-ml2 is an idle 96-core box
  while nh3-dev is a loaded 16-vCPU VM.
- **Bulk sequential streaming -> the link eats the win.** 4x read penalty against a
  6x CPU gain. `datasets/raw` is 126 GB, `datasets/derived` is 1.7 GB — which one the
  pipeline traverses changes the answer by two orders of magnitude. Staging a subset
  to ana-ml2 local disk (195 GB free) beats pulling it over the wire repeatedly.

The 24.7 MB/s is the Anaheim tunnel, not NFS and not the NAS — see
[[2026-08-23-anaheim-ipsec-tunnel-ceiling]]. No mount tuning will move it;
parallelism will.
