Avoid fragmentation of logical tapes when writing concurrently. Disk-based HashAgg relies on writing to multiple tapes concurrently. Avoid fragmentation of the tapes' blocks by preallocating many blocks for a tape at once. No file operations are performed during preallocation; only the block numbers are reserved.
Reviewed-by: Tomas Vondra Discussion: https://postgr.es/m/20200519151202.u2p2gpiawoaznsv2%40development Branch ------ master Details ------- https://git.postgresql.org/pg/commitdiff/896ddf9b3cd7dcf70e43f733ae8fec5dfe6e31af Modified Files -------------- src/backend/utils/sort/logtape.c | 80 ++++++++++++++++++++++++++++++++++++++-- 1 file changed, 77 insertions(+), 3 deletions(-)