MEMFLUSH(1)

💅 MEMFLUSH(1) 💅

okay so bestie, welcome to memflush from libmemcached-awesome — the manual page for the “nuke it and start fresh” command. it’s giving reset button energy, and yes, it’s iconic, but also please read the warning. 💀

✨ NAME ✨

memflush — libmemcached Documentation. that’s the whole name section, bestie: this is the libmemcached-awesome page for memflush. 💖

🛠️ SYNOPSIS 🛠️

memflush [options]

Reset a server or list of servers

💖 DESCRIPTION 💖

memflush resets the contents of memcached(1) servers.

WARNING: This means that all data in the specified servers will be deleted.

like… all of it. gone. no cap. so do a little vibe check before you run this, okay? 🫶

✨ OPTIONS ✨

• -h, --help — Display help. your little “what does this do again?” lifeline 🎀
• -V, --version — Display version. cute for checking what you’re working with ✨
• -q, --quiet — Operate quietly. less yapping, more doing 🤫
• -v, --verbose — Operate more verbosely. give me all the lore, bestie 🔍
• -d, --debug — See -v/--verbose. same energy, literally 🪞
• -s, --servers <list of servers> — Specify the list of servers as hostname[:port][,hostname[:port]...]. this is where you tell it which servers are catching the reset 💅
• -n, --non-blocking — Enable non-blocking operations.
• -N, --tcp-nodelay — Disable Nagle’s algorithm.
• -b, --binary — Enable binary protocol.
• -B, --buffer — Buffer requests.
• -u, --username <username> — Use username for SASL authentication.
• -p, --password <password> — Use password for SASL authentication.
• -e, --expire <expiration> — Use expiration seconds (or a UNIX timestamp).

NOTE: Using an expiration time (period), all keys, which have not bean updated until expiration will cease to exist.

and yes, “bean” is right there in the original — I’m not fixing the doc’s typo, I’m just delivering the content, bestie 💀

Quoting the memcached protocol documentation, it states:

Its effect is to invalidate all existing items immediately (by default) or after the expiration specified. After invalidation none of the items will be returned in response to a retrieval command (unless it's stored again under the same key after flush_all has invalidated the items).

The most precise definition of what flush_all does is the following: it causes all items whose update time is earlier than the time at which flush_all was set to be executed to be ignored for retrieval purposes.

The intent of flush_all with a delay, was that in a setting where you have a pool of memcached servers, and you need to flush all content, you have the option of not resetting all memcached servers at the same time (which could e.g. cause a spike in database load with all clients suddenly needing to recreate content that would otherwise have been found in the memcached daemon).

so yeah — delayed reset is a whole strategy, not just chaos. iykyk 🌸

🌈 ENVIRONMENT 🌈

• MEMCACHED_SERVERS — Specify a list of servers.

🏷️ NOTES 🏷️

🎀 PROGRAM PREFIX 🎀

The prefix of this program is variable, i.e. it can be configured at build time.

Usually the client programs of libmemcached-awesome are prefixed with mem, like memcat or memcp.

It can be configured, though, to replace the prefix with something else like mc; in case of that, the client programs of libmemcached-awesome would be called mccat, mccp, etc. respectively.

so if you see mc-something instead of mem-something, don’t panic — that’s just the build-time glow-up. ✨

👀 SEE ALSO 👀

memcached(1) libmemcached(3)

• C/C++ Client Library for memcached
• Wiping clean the contents of a server

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xoxo, your libmemcached-awesome bestie 💖 — this page is rockin’ version 1.1, dated Jul 18, 2024. periodt. 💅