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Docker, Memory Recommendations and Limitations

Hey so this is a new page that covers some basics that I get questions about fairly often and applies to most guides.

Container Manager or Docker?

The version of Diskstation Manager (DSM) you have installed on your Synology will define which Package for Docker itself is available to you.

Each of my guides has the appropriate icon on its featured image, so you know if you are following the correct one for your NAS.

For DSM versions 7.1 and below the package will be called Docker and have this icon – It can be installed via Package Center.

Container Manager is the new UI for Docker on DSM7.2 and above. It received a number of improvements over the previous Docker package including the ability to use Docker Compose from the UI. It can be installed via Package Center.

Memory Limitations and Performance Issues

Synology generally includes enough memory out of the box to get basic DSM features running and NAS file serving duties. For example the 220+ and 224+ come with 2GB of memory.

Once you start moving into ‘server’ duties with additional containers and packages you will hit memory limits very quickly. Even if DSM is showing X% of free memory it will begin using swap on disk which is extremely slow. Resulting in containers being sluggish, Plex or Jellyfin loading art at a snails pace and containers becoming unresponsive and causing intermittent connection issues between things such as Radarr and qBittorrent.

I would recommend upgrading to a minimum of 8GB of total RAM which will give you overall performance improvements. If you can afford to add more it will all be used as Linux also uses it for file caching.

Recommended Memory from our Discord Users

This list below is gathered directly from our Discord group and only added if someone is actively using that memory so no speculation around if it works.

Ensure you use the exact model number and not a variant, this list is updated as new submissions come in. (Last Update 10th March 2024)

24 Series

Model NoDSM Version TestedManufacturerModule Used
224+DSM 7.2.1Timetec1x16GB
224+DSM 7.2.1Timetec 1x16GB

23 Series

Model NoDSM Version TestedManufacturerModule Used
923+DSM 7.2Kingston1x16GB
423+DSM 7.2.1Crucial (Micron)1x8GB
423+DSM 7.2.1Timetek1x8GB
423+DSM 7.2.1Crucial (Micron)1x8GB
423+DSM 7.2.1Crucial (Micron)1x16GB
723+DSM 7.2.1Crucial (Micron)2x16GB

21 Series

Model NoDSM Version TestedManufacturerModule Used
1821+7.2Kingston 2x16GB
1821+7.2Crucial (Micron)2x16GB Kit
1821+7.2.1-69057 Update 4Team Group1x16GB
1821+7.2.1-69057 Update 4Timetec1x16GB 79TT26EUS2R8-16G

20 Series

Model NoDSM Version TestedManufacturerModule Used
1520+DSM 7.2Crucial (Micron)1x16GB Kit
1520+DSM 7.2.1Samsung1x16GB Kit
920+DSM 7.2Crucial1x8GB Kit
920+DSM 7.2Crucial1x16GB Kit
920+DSM 7.2Crucial1x16GB Kit
(Mixed results try other sticks)
920+DSM 7.2Crucial1x16GB
920+DSM 7.2Samsung1x16GB
720+DSM 7.2.1Kingston1x16GB
220+DSM 7.2Kingston1x16GB
220+DSM 7.2Crucial (Micron)1x8GB
220+DSM 7.2Crucial (Micron)1x16GB

18 Series

Model NoDSM Version TestedManufacturerModule Used
1019+DSM 7.2.1Crucial (Micron)2x8GB CT102464BF160B.C16

18 Series

Model NoDSM Version TestedManufacturerModule Used
918+DSM 7.2Samsung1x4GB
918+DSM 7.2SK Hynix1x4GB
718+DSM 7.2Crucial (Micron)2x8GB
218+DSM 7.2.1Crucial (Micron)1x8GB

16 Series

Model NoDSM Version TestedManufacturerModule Used
416playDSM 7.2.1Crucial (Micron)1x8GB

15 Series

Model NoDSM Version TestedManufacturerModule Used
1815+DSM 7.1.1Crucial (Micron)2x8GB
1515+DSM 6.xCrucial (Micron)2x8GB

12 Series

Model NoDSM Version TestedManufacturerModule Used
412+DSM 6.xKingston1x4GB


  1. Squishy Squishy

    I recently purchased this ram for the DS224+ and is workiong fine

    Integral RAM 16GB DDR4 2666Mhz SODIMM Laptop Notebook MacBook Memory

    Item model number – ‎IN4V16GNELSI

    I went from 6GB to 18GB and it has actually been a huge difference for docker, the Synology is way more snappier and fast now.

  2. Rahul Rahul

    Thanks for the comprehensive guides, not just this page. I will sure buy you some coffee.

    I have finally setup everything.. had ordered the RAM but installed all ARRs and plex in the mean time. Switching from PC to my Synology DS224+ with 2GB NAS… the experience was abysmal. Always had 80% -90% I/O wait and high disk activity continuously. As I waited for the RAM to come, was curious as to what I/O wait was. Decided to check reddit.. and so many were going on about how the drive must have bad sectors, asked to perform extended SMART tests or how it shouldn’t matter how much RAM you have.. everything should just work. I was second guessing my NAS purchase.

    After 3 weeks (I live far from US), the RAM came and minute I put it in.. had the whiplash of speed. Everything’s now running so smooth. Although now plex is eating up 14GB of RAM as cache(normal?), but rest of the containers are running smooth nevertheless.

    Anyways, thank you again for all your work.

    • Dr_Frankenstein Dr_Frankenstein

      Hey Rahul – First thanks for the coffee it is very much appreciated! 2 GB is such a low amount and only really suitable for very basic file serving. My Gaming PC in 2004 had 2 GB lol. Plex was likely what was thrashing the drives previously and now there will be enough for the system to swap out files in memory rather than disk.

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