Apologies for dropping in late here, but I just wanted to add a quick clarification about performance vCPUs (for anyone who might come across this) related to a question that came up earlier.
If a particular server has enough hardware CPUs to run all of the Machine vCPUs that are ready to run, then we’ll let all of them run at full speed. As a result, if the server that hosts your shared-vCPU Machine isn’t too busy at the moment, then your shared vCPU should run as fast as a performance vCPU. However, when there are more Machine vCPUs that are ready to run than there are hardware CPUs, then performance vCPUs get 4x the time to run, and consequently they’ll be much faster. Furthermore, we limit how many vCPUs can be allocated to a server, and performance vCPUs count the same as 4 shared vCPUs, so the worst-case performance of a performance vCPU is 4x better than a shared vCPU.
To summarize: if there’s extra CPU time available, then we’ll let shared vCPUs run faster, but if you depend on that, you may want to consider a performance vCPU.
In any case, I’m glad that you’ve figured out what was going on!