Memcached
Hacker ApprovedRanked 3 of 6 in-memory data stores by recommenders
Simple, fast, mature in-memory cache that people trust to do one job well. Caveat: slab configuration and memory use can cause operational trouble.
Simple, fast, mature in-memory cache that people trust to do one job well. Caveat: slab configuration and memory use can cause operational trouble.
37 people gave an opinion
- recommend it
- 27
- criticize it
- 10
- approval share
- 73%
Recommended in 6 of 13 months
- November 2025: recommended
- December 2025: not recommended
- January 2026: not recommended
- February 2026: recommended
- March 2026: not recommended
- April 2026: not recommended
- May 2026: recommended
- June 2026: recommended
- July 2026: not recommended
- August 2026: recommended
- September 2026: not recommended
- October 2026: recommended
- November 2026: not recommended (month in progress)
Why it carries the badge
- 27 people recommend itNeeds 10 or more, met.
- 2.7 recommenders for every criticNeeds 2 to 1 or better, met.
- Recommended in 6 of 13 monthsNeeds 4 or more, met.
The same three rules apply to every product, and the badge can’t be bought. How the badge works
What people say about it
The reasons people give, with the number of comments that give each one. Open a reason to read what they said.
Why people recommend it
Each mark is one comment
Simple and works out of the box
“It's cheap, reliable, mature, fast, scalable, requires little understanding, has decent quality clients in most languages”
Comment from 5 Feb 2026 in “It's 2026, Just Use Postgres” “Memcached by contrast is very simple, fast and works without needing to do much fiddling with it.”
Comment from 23 Jun 2026 in “In Praise of Memcached” “Memcached probably works better out of the box.”
Comment from 23 Jun 2026 in “In Praise of Memcached” - Comment from 23 Jun 2026 in “In Praise of Memcached”
Does one job well
“all operations are O(1) by design, which is a conscious design choice from the authors”
Comment from 23 Jun 2026 in “In Praise of Memcached” “memcached has always been the pinnacle of "choose boring technology"”
Comment from 23 Jun 2026 in “In Praise of Memcached” “it's highly optimized to do its one job super well”
Comment from 23 Jun 2026 in “In Praise of Memcached” - Comment from 6 Nov 2025 in “What the hell have you built”
Fast and scales per node
“It's cheap, reliable, mature, fast, scalable, requires little understanding, has decent quality clients in most languages”
Comment from 5 Feb 2026 in “It's 2026, Just Use Postgres” “Redis, memcached etc all can do 100k or more gets per second”
Comment from 23 Jun 2026 in “In Praise of Memcached” “memcached is multithreaded, so it scales up better per node.”
Comment from 5 Feb 2026 in “It's 2026, Just Use Postgres” Operationally straightforward pure cache
“memcached’s architecture in general more leans towards these directions, which makes it much, much more straightforward from an operations point of view”
Comment from 23 Jun 2026 in “In Praise of Memcached” “optional stateless pure cache with absolutely zero rope to hang yourself on”
Comment from 23 Jun 2026 in “In Praise of Memcached” “I'd use memcached or some equivalent for strictly cacheing”
Comment from 23 Jun 2026 in “In Praise of Memcached”
What people warn about
Each mark is one comment
Client libraries and sharding burden
“With memcached I remember having to mess around the LD_LIBRARY path”
Comment from 23 Jun 2026 in “In Praise of Memcached” “each client did it's own hashing/sharding system”
Comment from 23 Jun 2026 in “In Praise of Memcached” “memcached libary was unmaintained”
Comment from 6 Mar 2026 in “Good software knows when to stop” - Comment from 23 Jun 2026 in “In Praise of Memcached”
Slab configuration and starvation problems
“Memcache is great until you get into the business of having to configure slabs.”
Comment from 23 Jun 2026 in “In Praise of Memcached” “The memcache slab pools are a leaky abstraction that you may end up having to manage operationally”
Comment from 23 Jun 2026 in “In Praise of Memcached” “Google "memcache slab starvation" if you want the long story”
Comment from 23 Jun 2026 in “In Praise of Memcached” Crashes and failures under load
“it would have low cpu utilization then unexpectedly hit lock contention and fall over without warning”
Comment from 23 Jun 2026 in “In Praise of Memcached” “Literally every one of these has caused hilarious and disastrous failures for me in my career.”
Comment from 13 Aug 2026 in “Choose Boring Technology (2015)” “fixing memory-leak-caused kube memcached crashes is steeper”
Comment from 16 Jun 2026 in “What job interviews taught me about Kubernetes”
Other in-memory data stores people recommend
The four most recommended other in-memory data stores, with the same counts for each, so you can compare like for like. The tick on each bar marks the 2 to 1 line the badge needs.
| Product | Recommend | Criticize | Approval | Months | Owned | Badge |
|---|---|---|---|---|---|---|
| Redis | 174 | 102 | 63% | 12 | 10 yrs7 owners | — |
| Valkey | 31 | 5 | 86% | 10 | — | Approved |
| MemcachedThis page | 27 | 10 | 73% | 6 | — | Approved |
| Lux Redis-compatible server | 8 | 7 | 53% | 2 | — | — |
| KiviDB | 7 | 2 | 78% | 1 | — | — |
What people said
35 of the 39 comments that mention it, newest first. Each links to the original comment.
“it is also a replacement to memcache which kividb isn't yet”
“I've gotten a ton of use out of memcached over the years”
“Literally every one of these has caused hilarious and disastrous failures for me in my career.”
“It sped up pages, and just worked.”
“There's nothing about memcache that avoids these problems.”
“each client did it's own hashing/sharding system”
“We pulled the cache layer into memcached.”
“Burning memory for a pure memory/RAM service like memcached in today's environment is not going to work given the price of memory”
“Redis, memcached etc all can do 100k or more gets per second”
“Memcached by contrast is very simple, fast and works without needing to do much fiddling with it.”
“Google "memcache slab starvation" if you want the long story”
“memcached has always been the pinnacle of "choose boring technology"”
“it's highly optimized to do its one job super well”
“Memcache is great until you get into the business of having to configure slabs.”
“I'd use memcached or some equivalent for strictly cacheing”
“all operations are O(1) by design, which is a conscious design choice from the authors”
“I like memcached, but its really not redis's fault if you set it up as a volatile cache”
“I don't think memcached is bad, I just think its old”
“optional stateless pure cache with absolutely zero rope to hang yourself on”
“With memcached I remember having to mess around the LD_LIBRARY path”
“It can be difficult to architect an app to have a memcache-friendly cache layout.”
“Never felt the need to go back to memcached except when a legacy dependency needed it.”
“The memcache slab pools are a leaky abstraction that you may end up having to manage operationally”
“Memcached probably works better out of the box.”
“it would have low cpu utilization then unexpectedly hit lock contention and fall over without warning”
“memcached’s architecture in general more leans towards these directions, which makes it much, much more straightforward from an operations point of view”
“fixing memory-leak-caused kube memcached crashes is steeper”
“Use apc or memcached for persistent storage.”
“A 30 second memcached/redis/etc goes a long way when sharing on HN.”
“memcached libary was unmaintained”
“memcached is multithreaded, so it scales up better per node.”
“It's cheap, reliable, mature, fast, scalable, requires little understanding, has decent quality clients in most languages”
“memcached would probably increase that by several orders of magnitude”
“setting up nginx, memcached, LAMP stacks”
“far simpler solution that provides 99% of what you need in practice”
Counts come from 1,795,640 Hacker News comments, November 2025 to November 2026. How we count. Report a mistake.