Interesting. Paz, I kind of think this is worth bringing to the attention of those on the 'EPICS discussion' thread about improving workflows/nexus handling, do you agree? Steve From: Sarah Foxley - STFC UKRI &lt;sarah.foxley(a)stfc.ac.uk&gt; Sent: 22 February 2024 15:27 To: mpb(a)mantidproject.org Subject: [Mpb] ORNL Nexus work Dear all, One of the actions on me from the last meeting was to provide an update on the Nexus work that ORNL are doing. For 6.10 they are planning to undertake a new implementation of LoadEventNexus. This was found to be the slowest step in many of their workflows. Investigation of this algorithm found it was spending much of its time doing other things than reading from disk. The suggested solution is to move away from the current method of allocating all the events and then reusing code for sorting and compressing. Instead they plan to create a histogram whilst reading through events and then converting that data to an EventList. There will be instances where this new method will not be used: - Small event files - Files with period data - Files with weighted events There is much more detail about their plans here - https://github.com/mantidproject/mantid/issues/36594 . Let me know if you have any questions about this and I will follow up with Pete at ORNL. All the best Sarah Sarah Foxley Mantid Team Leader and Mantid Project Manager Science and Technology Facilities Council Phone - 01235 446938 sarah.foxley@stfc.ukri.org<mailto:sarah.foxley@stfc.ukri.org> She/Her/Hers [stfc_logo]