Cloud Drive Mount Caching: Why It Matters and How It Works

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The naive mount problem

If you mount a cloud drive and try to edit a 4K video, you hit a wall: every scrub is a network round-trip, every save is a network round-trip. The mount feels useless for real work.

The fix: local cache.

What is a mount cache?

A local cache is a directory on a fast local SSD where the mount client stores recently read or written blocks. On the second open, the file reads from local disk, not the cloud. On write, the client pushes back to the cloud asynchronously.

This makes the mount feel local for hot files, while keeping the cloud as the source of truth.

How it works in ScsDriver

ScsDriver's local cache is configurable:

• Cache directory: pick a fast SSD with space
• Cache size: limit (e.g. 50GB). Old blocks are evicted LRU.
• Eviction policy: LRU (least recently used) by default
• Streaming mode: large files (>100MB) are read in chunks, not held entirely in cache

When you open a file:

1. Check if the file is in the local cache. If yes, read from cache.
2. If not, fetch the file from the cloud and store in cache for next time.
3. Return the data to the requesting app.

When you save a file:

1. Write to the local cache immediately (returns fast).
2. Push the updated block to the cloud asynchronously.
3. On next open, the cache has the latest version.

What this means for editing

Premiere opens a 4K clip. Without cache, every scrub triggers a network fetch. With cache, the first read pulls the file (slow, but once), and subsequent scrubs are local.

For a 50GB project, the first open is slow (one-time network fetch). Every subsequent open is fast.

When to enable streaming mode

Streaming mode reads large files in chunks, so you don't have to download the whole file before you can start editing. This is critical for video editing:

• Without streaming: open a 50GB clip → wait 10 minutes for full download → can scrub
• With streaming: open a 50GB clip → wait 5 seconds for first chunk → can scrub the start → rest downloads in background

Set "Streaming mode" on in ScsDriver settings for video editing.

When cache hurts

Caching is great for hot files. It's not great for:

• Cold archives: 10TB of files you touch once. Don't cache them.
• Write-only targets: backup drives. You don't read them back.
• Strict consistency: if you need every write to be on the cloud before the next read (rare), disable cache.

For most editing workflows, cache is strictly better.

Cache tuning for your SSD

If you have a fast NVMe, point ScsDriver's cache there:

• Cache directory: D:\WebDAVCache (D: is your NVMe)
• Cache size: 50-100GB (you have 1TB+, easy)
• Enable streaming mode

If you only have a SATA SSD or HDD, be more conservative:

• Cache size: 10-20GB
• Streaming mode off (too slow to be useful)

Verdict

Local cache is the difference between a mount that feels local and a mount that feels like a network drive. ScsDriver's cache is well-implemented and configurable. For $5.5 lifetime (was $9.99), it's the cheapest way to get cache + mount on Windows / macOS.

For users in mainland China, the package is sold at CN ¥20 lifetime (separate pricing region).

Pricing recap (overseas)

• $1.5 monthly
• $5.5 yearly
• $5.5 lifetime (was $9.99)

For users in mainland China, the package is sold at CN ¥20 lifetime (separate pricing region).