mssql_server_tiny

what

• a slightly modified Microsoft SQL Server docker image
  • modified to allow execution on a machine with less than 2 GiB of physical memory

why

• Microsoft's sqlservr, at startup, looks to see how much physical memory its host has
• if the host has less than 2 GiB sqlservr just quits with the message:
  • "sqlservr: This program requires a machine with at least 2000 megabytes of memory."
• it turns out that sqlservr does not try to allocate that much memory and fail but rather sqlservr enforces that as a policy (perhaps to cut down on performance related issues due to page faulting)
• but i think if someone wants to use swap space instead of physical memory that is up to that person

how

• using LD_PRELOAD to redefine the system call "sysinfo"
• when sqlservr invokes the "sysinfo" system call (to see how much physical memory the host has) we instead lie to sqlservr with our redefined sysinfo function

how to use

• pull from docker hub's build of this repository:
  • docker run -e 'ACCEPT_EULA=Y' -e 'SA_PASSWORD=yourStrong(!)Password' -p 1433:1433 -d justin2004/mssql_server_tiny
• or build this image yourself

---

• https://hub.docker.com/_/microsoft-mssql-server
• https://github.com/Microsoft/mssql-docker