# Cache Metrics

Learn how Supabase Storage caches objects with a CDN.

Cache hits can be determined via the `log_attributes['response.headers.cf_cache_status']` key in [Query logs with SQL](/docs/guides/observability/advanced-log-filtering#logs-explorer). Any value that corresponds to either `HIT`, `STALE`, `REVALIDATED`, or `UPDATING` is categorized as a cache hit.
The following example query will show the top cache misses from the `edge_logs`:

```sql
select
  log_attributes['request.path'] as path,
  log_attributes['request.search'] as search,
  count() as count
from logs
where source = 'edge_logs'
  and startsWith(log_attributes['request.path'], '/storage/v1/object')
  and log_attributes['request.method'] = 'GET'
  and log_attributes['response.headers.cf_cache_status'] in ('MISS', 'NONE/UNKNOWN', 'EXPIRED', 'BYPASS', 'DYNAMIC')
group by path, search
order by count desc
limit 50;
```

Run this query in [Explorer](/dashboard/project/_/explorer): select **Run SQL**, choose query source **Logs**, and set a time range.

Your cache hit ratio over time can then be determined using the following query:

```sql
select
  toStartOfHour(timestamp) as timestamp,
  countIf(log_attributes['response.headers.cf_cache_status'] in ('HIT', 'STALE', 'REVALIDATED', 'UPDATING')) / count() as ratio
from logs
where source = 'edge_logs'
  and startsWith(log_attributes['request.path'], '/storage/v1/object')
  and log_attributes['request.method'] = 'GET'
group by timestamp
order by timestamp desc
limit 100;
```

Run this query in [Explorer](/dashboard/project/_/explorer): select **Run SQL**, choose query source **Logs**, and set a time range.