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by crazygringo 461 days ago
> Latency and bandwidth can be made 10x worst by process context switching alone.

No they can't. That doesn't even make sense as a claim regarding bandwidth since SQLite doesn't use any, but please re-read what I said about being a 1% or 5% difference in speed. Not 10x.

1 comments

Yes they absolutely can.

Same-core context switching costs a few microseconds.

Going across core complexes can cost tens to hundreds of microseconds.

These figures are several orders of magnitude (5-6) slower than L1 access on the same thread.

Hundreds of microseconds? L1 access? I don't have the faintest idea of what you're talking about.

Communication between processes is negligible compared to all of the sequential disk/SSD accesses and processing required for executing queries.

The database isn't stored in L1 and communication isn't taking hundreds of microseconds. I don't know where you're getting your information.

The fact that SQLite is in-process is primarily about simplicity and convenience, not performance. Performance can even be worse, e.g. due to the lack of a query cache.