Caching layers (Redis / Memcached)
We implement an in-memory caching layer (Redis or Memcached): frequently requested data, heavy-query results, sessions and fragments are stored in fast memory, offloading the database and application. So responses are faster and the DB does not crash under load. Honestly upfront: a cache greatly speeds up repeat reads, but the main difficulty is invalidation (not serving stale data), it needs separate infrastructure (a Redis server) and not everything is cached.
Caching layers (Redis / Memcached) — overview
Caching layers is an implementation project: we deploy/connect Redis or Memcached, determine what to cache (heavy-query results, reference data, sessions, page fragments, computations), set up keys, TTL and an update strategy (event/tag invalidation, warming), integrate it into the application. Honestly about the main difficulty, this is key: 'in a cache the hard part is not writing but invalidation' — serving stale data (an old price, stock, content) is worse than not caching; so the core of the work is correct cache updating/clearing, and we test this thoroughly. Honestly about infrastructure and cost: a Redis/Memcached server is needed (memory is a resource); it is separate infrastructure and its cost (your own server or a managed service) — separate from our work; not available on all hosting. Honestly about limits: what is cached is what can be safely reused; personalized/constantly changing data is cached to a limited extent; a cache does not cure inherently bad queries (they should be optimized first — 717). Honestly about risk: on a cache failure/overflow the application must work correctly with the DB (graceful fallback) — we build this in. Honestly about the effect: for cacheable content the win is large and measurable (DB offload, fast response), but we do NOT guarantee sales growth by itself. Honestly about access: access to the server/code is needed. An important boundary: this is in-memory application cache, not server page/opcode caching in general (720 — adjacent), not CDN edge cache (714) and not query optimization (717). If load is low and data is not reused, a cache is overkill. Picture this: instead of 'a heavy DB query every time' — instant serving from memory, without stale data. The base price starts from 22,000 ₽ per project; it depends on the caching scope and integration (Redis infrastructure — separate).
Problems we solve
- The DB is overloaded by repeated heavy queries.
- Under load the site lags or crashes.
- Frequently requested data is recomputed every time.
- Sessions/reference data are not cached, everything hits the DB.
What's included in the Caching layers (Redis / Memcached) service
- Deploying/connecting Redis or Memcached
- Determining what is safe to cache
- Setting up keys, TTL and an invalidation strategy
- Cache warming and graceful fallback on failure
- Integration into the application
- Thorough freshness testing (no stale data)
- A 'before/after' report by load/response
- Handover and review with you
What you get
- Fast serving of frequently requested data from memory
- DB offload and resilience under load
- Correct invalidation — without stale data
- Fault tolerance on cache failure (sales growth — not guaranteed)
How the work goes: steps
- We clarify the load, what to cache, infrastructure; collect access
- We connect Redis/Memcached, set up keys/TTL/invalidation/fallback
- We test freshness and the effect, review with you
Why PDV Expert
- Fixed price and timeline — no surprises on the invoice.
- Report and recommendations in plain language — clear without a technical background.
- In touch at every step and answering questions about the result.
FAQ
What is the hardest part of a cache?
Invalidation — correct updating. Serving a stale price/stock is worse than not caching. So the core of the work is update strategies and tests, so the user does not see old data. Writing to the cache is easy, freshness is not.
Is the Redis server included in the price?
No. Separate infrastructure is needed (your own Redis/Memcached server or a managed service) — a resource and cost separate from our work; not available on all hosting. We do the setup and integration.
Will a cache speed up everything?
No. What is cached is safely reusable; personalized/constantly changing data is limited. And a cache does not cure inherently bad queries — they should be optimized first (a separate service). We do not guarantee sales growth by itself.
About the provider
The «Caching layers (Redis / Memcached)» service is provided by PDV Expert — a team specialising in «Site quality». We work under contract and deliver a written report with recommendations.