pnorbert

Thanks for the explanation. So you can/want to use extra processes that act as IO processes and do the staging from the application processes to the IO processes asynchronously, and...

BP readers simply remove all variable definitions in EndStep to make sure they don't linger around. Reading outside of BeginStep..EndStep is invalid. And in the next BeginStep, a new set...

Thank you for the observation. We never had the O_DIRECT flag as it destroys performance on Lustre/GPFS parallel file systems. They like their buffering mechanisms to be used. So, we...

@DominicWindisch If we need to change file format, we need to talk asap about BP5, which is one month from release. The data files there are aligned already (aligment size...

in BP5, a parameter FileSystemPageSize controls the alignment of buffers (each buffer in a vector of buffers). The default value right now is 4096 so this should already cover your...

testing is not too early. We want to release BP5 in a month, so any modification to the file format itself should get into it before that. Although it looks...

@DominicWindisch We added DirectIO support to BP5. When PR #3053 is merged into master, would you mind to try it out on your system? The BP5 parameters are ``` io.SetEngine("BP5");...

re. min/max chunk size: [this is for AIX](https://www.ibm.com/docs/de/aix/7.2?topic=io-benefits-direct)

@DominicWindisch Can you please give us some feedback on this in a couple of weeks? We are almost ready for code freeze and we plan to have a release soon....

Thank you for the measurements. Are your buffers (`data`) already aligned properly? In the current implementation we force copy of data into the aligned internal buffers when directio is turned...