umbra

Measure the time for the Moon to move from touching the umbra to completely exiting the umbra.

Earth's Umbra Length: The tip of Earth's main, total shadow (the umbra) ends before it reaches the \(L_{2}\) point, usually around 92% of the distance to \(L_{2}\).

For those also in Toronto, you can pick them up at the Umbra showroom off Queen and John.

You only have to be in the location of the Moon's umbra as it passes over the Earth.

Does anyone have any Umbra experience and can say how well it works for things that are not DBT-3?

I'm a bit late, but: Umbra doesn't use AsmJIT anymore since many years, it was too slow.

Solar Exposure: Because \(L_{2}\) is outside the full umbra, a satellite at this location (like the James Webb Space Telescope) is never in total darkness.

Salesforce's Hyper for example very heavily relies on JIT compilation, as does Umbra [1], which some people regard as one of the fastest databases right now.

The part of Umbra I found interesting was the buffer pool, so that's where focused most of my attention when reading though.

My understanding is the research projects LeanStore & Umbra -- and now I assume the product CedarDB based on the people involved, etc.

If I recall research papers regarding Umbra it's also using AsmJit as a JIT backend, which means that theoretically the compilation times would be comparable if you only consider code emitting overhead.

The ideal would be to park the data centers at the lagrange point behind the Earth in its umbra, so they don't need to dissipate direct solar heat.

"Top Secret Umbra" I haven't seen that code word since I worked at a communications monitoring site in Turkey in 1977.

Yeah I think the way Umbra was pitched when I watched the talks and read the paper was as more as "hybrid" in the sense that it aimed for something close to in-memory performance while optimizing the page-in/page-out performance profile.

I could have sworn I had read these things about Umbra, but I suppose it was HyPer.

Umbra doesn't cache any IR or compiled code and still has an extremely low start-up latency; an interpreter exists but is practically never used.

Umbra is not an in-memory database (Hyper was).