Redis Hash Limits?
Chris Johnson
To revisit the subject of Redis limits, what is the limit on:
(1) Number of hashes in redis?
(2) The number of fields within a given Redis hash?
I would imagine that each answer would be 2^32 (~4 billion), but I
wanted to verify.
As an aside, I wanted to share the nature of the data I'll be storing
in hashes, and I am hoping that if the hash structure is sub-optimal you
might be able to suggest an alternative:
Hash Name: "user_views:#{Date.today}:#{partner_id}" (planning on
about 5,000 different partner_ids)
Field: "#{user_id}" (planning about 10,000,000 user_ids, per partner)
Value: <a running total of views, modifying with hincrby>
>>
Cheers.
Chris
findchris
To revisit the subject of Redis limits, what is the limit on:
(1) Number of hashes in redis?
I would imagine that each answer would be 2^32 (~4 billion), but I
wanted to verify.
As an aside, I wanted to share the nature of the data I'll be storing
Hash Name: "user_views:#{Date.today}:#{partner_id}" (planning on
about 5,000 different partner_ids)
findchris
findchris
to this group.
Salvatore Sanfilippo
> To revisit the subject of Redis limits, what is the limit on:
> (1) Number of hashes in redis?
> (2) The number of keys within a given Redis hash?
Hello, figures looking directly at the code:
1) Number of keys in every Redis database: 2^64-1 in 64 bit systems.
2^32-1 in 32 bit systems.
2) Number of hash fields in every hash: 2^64-1 in 64 bit systems.
2^32-1 in 32 bit systems.
Given that a 32 bit instance has at max 4GB of addressable space, the
limit is unreachable.
For 64 bit instances, given how big is 2^64-1, the limit is unreachable.
So for every practical point of view consider keys and hashes only
limited by the amount of RAM you have.
Salvatore
--
Salvatore 'antirez' Sanfilippo
open source developer - VMware
http://invece.org
"We are what we repeatedly do. Excellence, therefore, is not an act,
but a habit." -- Aristotele