ZNC Memory Usage

This page is intended to give users an idea and rough estimate of how much memory ZNC needs to run. Other users are asked to provide anecdotal reports which include memory usage as well as other relevant information.

Various factors can affect ZNC memory usage, including:

• Number of channels (across all users on a ZNC instance)
• Average saved buffer size of each channel
• Whether the AutoClearChanBuffer setting is used
• Query Buffers (if ZNC 1.5 or later)
• Loaded modules (number, type, and function)
• Number of users
• System architecture (x86, x86-64, etc.)

Note: These are anecdotal reports, which are personal experiences of other ZNC users/administrators. These reports are not in any way verified, nor are any of them the least bit scientific. If exact resource usage figures are important, performing your own testing is highly recommended. As always, YMMV.

The following list doesn't include a list of modules used in each case for the sake of brevity. However, module use could have a meaningful effect on memory usage.

ZNC Version	Memory Usage	Number of channels	Average Buffer Size	AutoClearChanBuffer	Number of Users	System Arch
1.4	60.9 MB	About 260	About 2,000	Yes, mostly	9	x86-64 (Debian 7.7)
1.4	27.8 MB	About 100	About 100	Yes, mostly	8	x86-64 (Debian 7.7)
1.5	12.1 MB	About 20	About 850,000	Yes	1	x86-64 (Slackware 14.1)
1.5	7.3 MB	About 30	About 4,290,032,704	Yes	4	x86-64 (Ubuntu 13.10)
1.6.5	160 MB	About 100	50	Yes	1	x86-64 (Debian 8)
1.6.5	57 MB	About 100	50	Yes	2	x86-64 (Debian 8)
1.7.x-git*	324.75 MB	Over 200	About 50 - 100	Yes	57	x86-64 (Ubuntu 17.04)
1.7.x-git	50.2 MB	53	About 1,000,000	Yes	2	x86-64 (Ubuntu 14.04.5 LTS)
1.7.x-git [ZNC-Linker bot]	7.9 MB	2	About 50	Yes	1	x86-64 (Ubuntu 14.04.5 LTS)
1.7.x-git	4.7 MB	9	About 500	Yes	1	x86-64 (Ubuntu 14.04.5 LTS)
1.7.x-git	10.3 MB	10	About 50	Yes	1	x86-64 (Ubuntu 16.04.2 LTS)
1.7.x-git	7.7 MB	7	About 50	Yes	1	x86-64 (Ubuntu 16.04.2 LTS)