lmcache quota

The lmcache quota command manages per-salt cache quotas on a running LMCache server. Quotas are soft limits: exceeding a quota triggers eviction on the next cycle (~1 s) rather than rejecting writes.

lmcache quota <sub-command> [options]

$ lmcache quota -h
usage: lmcache quota [-h] {set,get,list,delete} ...

Manage per-salt cache quotas on the LMCache server.

subcommands:
  set            Create or update a quota for a cache_salt
  get            Show the quota and current usage for a cache_salt
  list           List all registered quotas and their usage
  delete         Remove a quota for a cache_salt

options:
  -h, --help     show this help message and exit

set

Create or update a quota for a given cache_salt.

lmcache quota set <salt> --limit-gb <GB> [--url <URL>]

Example:

$ lmcache quota set tenant1 --limit-gb 10.5

================ Quota Set =================
Cache salt:                          tenant1
Limit (GB):                             10.5
Status:                                   ok
=============================================

Options:

Flag	Required	Description
<salt>	Yes	The cache_salt identifier. Use _default for anonymous (un-salted) traffic.
--limit-gb	Yes	Quota limit in gigabytes (non-negative float).
--url	No	LMCache HTTP server URL (default: http://localhost:8080).
--format	No	Output format: terminal (default) or json.
--output	No	Save output to a file (uses the format chosen by --format).
-q / --quiet	No	Suppress stdout output. Exit code only.

get

Show the current quota limit and live usage for a specific cache_salt.

lmcache quota get <salt> [--url <URL>]

Example:

$ lmcache quota get tenant1

================ Quota Info ================
Cache salt:                          tenant1
Limit (GB):                             10.5
Current usage (GB):                     3.27
Exists:                                 True
=============================================

Options:

Flag	Required	Description
<salt>	Yes	The cache_salt identifier.
--url	No	LMCache HTTP server URL (default: http://localhost:8080).
--format	No	Output format: terminal (default) or json.
--output	No	Save output to a file.
-q / --quiet	No	Suppress stdout output.

list

List all registered quotas along with their current usage.

lmcache quota list [--url <URL>]

Example:

$ lmcache quota list

=================== Quota List ====================
--- Salt: tenant1 ---
Cache salt:                               tenant1
Limit (GB):                                  10.5
Current usage (GB):                          3.27
--- Salt: _default ---
Cache salt:                              _default
Limit (GB):                                   5.0
Current usage (GB):                          1.82
===================================================

JSON output:

$ lmcache quota list --format json
{
  "title": "Quota List",
  "sections": {
    "quota_0": {
      "label": "Salt: tenant1",
      "metrics": {
        "cache_salt": "tenant1",
        "limit_gb": 10.5,
        "current_usage_gb": 3.27
      }
    },
    "quota_1": {
      "label": "Salt: _default",
      "metrics": {
        "cache_salt": "_default",
        "limit_gb": 5.0,
        "current_usage_gb": 1.82
      }
    }
  }
}

Options:

Flag	Required	Description
--url	No	LMCache HTTP server URL (default: http://localhost:8080).
--format	No	Output format: terminal (default) or json.
--output	No	Save output to a file.
-q / --quiet	No	Suppress stdout output.

delete

Remove a quota entry for a given cache_salt. Any bytes still cached under this salt become over-budget on the next eviction cycle and will be evicted (effective limit drops to 0).

lmcache quota delete <salt> [--url <URL>]

Example:

$ lmcache quota delete tenant1

============== Quota Delete ===============
Cache salt:                        tenant1
Status:                            removed
===========================================

Options:

Flag	Required	Description
<salt>	Yes	The cache_salt identifier.
--url	No	LMCache HTTP server URL (default: http://localhost:8080).
--format	No	Output format: terminal (default) or json.
--output	No	Save output to a file.
-q / --quiet	No	Suppress stdout output.

Exit Codes

Code	Meaning
0	Success.
1	Error (connection failure, server error, bad arguments).

The _default Salt

The LMCache server uses an empty string ("") as the cache_salt for anonymous / un-salted traffic. Since empty strings cannot appear in URL path parameters, the HTTP API (and this CLI) uses the sentinel _default in its place.

# Set a 5 GB quota for anonymous traffic
lmcache quota set _default --limit-gb 5.0

# Check usage
lmcache quota get _default

Common Patterns

Provision quotas for multiple tenants:

for tenant in tenant_a tenant_b tenant_c; do
    lmcache quota set "$tenant" --limit-gb 8.0
done

Monitor usage in a script:

USAGE=$(lmcache quota get tenant1 --format json | jq '.metrics.current_usage_gb')
LIMIT=$(lmcache quota get tenant1 --format json | jq '.metrics.limit_gb')
echo "tenant1: ${USAGE} / ${LIMIT} GB"

Revoke access (evict all cached data for a salt):

# Deleting the quota causes all data under this salt to be evicted
lmcache quota delete tenant1