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--- parallel-io-mpi [June 11, 2026 at 09:10] – created - external edit 127.0.0.1
+++ parallel-io-mpi [June 11, 2026 at 09:12] (current) – Ivan Janevski
@@ Line 1: / Line 1: @@
 # Parallel I/O (MPI)
-POSIX `pwrite(fd, buf, n, offset)` lets multiple processes write to different offsets in the same file without interfering: the offset is passed explicitly rather than shared, so there is no race on the file position. The straightforward approach in a parallel program is for each process to compute its own offset and call `pwrite` directly. MPI-IO builds on the same idea but adds a collective interface: each process opens the same file with `MPI_File_open` and writes its portion with an explicit offset. The advantage of the collective call `MPI_File_write_at_all` is that the runtime can merge small contributions from all processes into fewer, larger I/O operations aligned to filesystem stripe boundaries.
+POSIX `pwrite(fd, buf, n, offset)` lets multiple processes write to different offsets in the same file without interfering: the offset is passed explicitly rather than shared, so there is no race on the file position. The straightforward approach in a parallel program is for each process to compute its own offset and call `pwrite` directly.
+MPI-IO builds on the same idea but adds a collective interface: each process opens the same file with `MPI_File_open` and writes its portion with an explicit offset. The advantage of the collective call `MPI_File_write_at_all` is that the runtime can merge small contributions from all processes into fewer, larger I/O operations aligned to filesystem stripe boundaries.
 ```c