Ubuntu
memtest86+ package

  1. Bug #1876157
  2. Comment #36

Comment 36 for bug 1876157

Revision history for this message
Phil Marsh (marsh-pf) wrote :

Ubuntu maintainers,
Thanks for your software and service to us all!
Please, Please, Please stop shipping Memtest86+ version 5.31b with Ubuntu.
From my experience, this software IS NOT threadsafe and will falsely report RAM errors when RAM is OK. I think this happens because, in mult-core (multithread) mode, i.e. use all CPU cores in parallel, the software allows simultaneous reads and writes to a RAM location which corrupts the RAM, causing indeterminate values to be read. These are of course, interpreted as RAM errors, even though the RAM is sound.

I verified this by running Memtest86+ version 5.31b in multicore mode (default that shipped with Xubuntu 22.04) on my E5-2690v4 and E5-2697v3 based servers with DDR4 RAM. The Xubuntu Memtest86+ showed several RAM errors after 30min to 5hrs of running. Memtest86+ running one CPU round-robin showed no errors. Also, Memtest86 version 10.0 (a different vendor than Memtest86+) showed no errors in multicore mode running for 24hrs on both machines.
To users: DO NOT trust Memtest86+ multi-core mode. Use single-core mode only OR better use Memtest86 version 10.0 (latest version) and run that in parallel, multicore mode.