jungfrauandClaude Opus 5
0fed94d75b
Post-refinement fits eight numbers, and it selects the twenty thousand best-recorded events to fit them from. Before it can select, it copies every integrated partial into an array of its own and sorts it. On a large cell that is 63 million of them, and the phase took 8.5 s of a 56 s run. Almost none of that was the sort. `std::vector<Partial> pts(n)` value-initialises: one thread writes 3.5 GB of zeroes, page by page, before the parallel fill overwrites every byte of it - and being the first touch, it also decides where the pages live, so the whole array lands on one NUMA node and every later pass over it runs at one node's bandwidth. The same again for the sorted copy. Allocate the storage without initialising it and let the parallel fill be the first touch. The record itself carried more than the sort reads. `angle_rad` is a function of the image number that the goniometer can give back on demand, and the two observed positions are wanted only by the distance step, and only for the twenty thousand it keeps. Storing what is read - and as the floats the fields already were, since widening a float to a double is exact - takes the record from 56 bytes to 32, which is a third off the fill and half off the sort's element moves. Then three passes that walked the whole array to no purpose. The h range is now taken in the count pass, which reads the same reflections anyway; the bucket histogram in the fill pass, which already has h in hand. The event split walked serially and grew its output by doubling - about a gigabyte of pure copying - although h is the leading sort key, so a rocking event never crosses an h bucket: count per bucket, prefix, fill in parallel, and the events come out in the order the serial walk produced them. And the copy of the whole event list, made only so that nth_element could destroy the original, is now an index array. Every one of these is the same arithmetic in the same order. Measured on a large-cell rotation set, with the two commits that follow: 52.6 s -> 46.1 s, and the merged .hkl, .mtz and .cif are byte-identical. `part_less` is deliberately left as it was, not a total order: what makes it reproducible is that each bucket reaches the sort in gather order, and the new chunking is still a contiguous span of that order. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_011n8riB6X59oRjkrSHzNPAU
Jungfraujoch
Application to receive data from the PSI JUNGFRAU and EIGER detectors.
All documentation is now placed in docs/ subdirectory and for the current version hosted on Jungfraujoch Read The Docs page.