pgsql: Provide vectored variants of smgrread() and smgrwrite().
Provide vectored variants of smgrread() and smgrwrite(). smgrreadv() and smgrwritev() and their md.c implementations call FileReadV() and FileWriteV(). A range of disk blocks beginning at 'blocknum' and extending for 'nblocks' can be scattered to or gathered from multiple buffers with a single system call. The traditional smgrread() and smgrwrite() functions are implemented in terms of the new functions. Later commits will introduce calls with nblocks > 1, but the following behavioral changes can be seen already: * After a short transfer we'll now retry until we eventually read 0 bytes (= EOF) or get ENOSPC, EDQUOT, EFBIG etc, where previously we would infer the reason. Retrying is consistent with xlog.c's treatment of large WAL writes, and arguably also xlog.c and fd.c's treatment of EINTR. Arbitrary short returns for larger transfers have been observed on several OSes, and might in theory also happen for transient reasons with our own pg_p*v() fallback code. * After unexpected EOF or -1, the error thrown now talks about a range even for the single block case, eg "blocks 42..42". Reviewed-by: Heikki Linnakangas Discussion: https://postgr.es/m/CA+hUKGJkOiOCa+mag4BF+zHo7qo=o9CFheB8=g6ut5tum2g...@mail.gmail.com Branch -- master Details --- https://git.postgresql.org/pg/commitdiff/4908c5872059c409aa647bcde758dfeffe07996e Modified Files -- doc/src/sgml/monitoring.sgml| 4 +- src/backend/storage/smgr/md.c | 325 src/backend/storage/smgr/smgr.c | 37 ++--- src/include/storage/md.h| 9 +- src/include/storage/smgr.h | 25 +++- 5 files changed, 279 insertions(+), 121 deletions(-)
pgsql: Doc: add a bit to indices.sgml about what is an indexable clause
Doc: add a bit to indices.sgml about what is an indexable clause. We didn't explain this clearly until somewhere deep in the "Extending SQL" chapter, but really it ought to be mentioned in the introductory material too. Discussion: https://postgr.es/m/4097442.1694967...@sss.pgh.pa.us Branch -- REL_13_STABLE Details --- https://git.postgresql.org/pg/commitdiff/b4c147ac6fd5238d2c49b6369d555f29dbfc9144 Modified Files -- doc/src/sgml/indices.sgml | 35 ++- 1 file changed, 34 insertions(+), 1 deletion(-)
pgsql: Doc: add a bit to indices.sgml about what is an indexable clause
Doc: add a bit to indices.sgml about what is an indexable clause. We didn't explain this clearly until somewhere deep in the "Extending SQL" chapter, but really it ought to be mentioned in the introductory material too. Discussion: https://postgr.es/m/4097442.1694967...@sss.pgh.pa.us Branch -- REL_14_STABLE Details --- https://git.postgresql.org/pg/commitdiff/7a4bdd986ab9a10f3bc2d8875be6e154b63a1918 Modified Files -- doc/src/sgml/indices.sgml | 35 ++- 1 file changed, 34 insertions(+), 1 deletion(-)
pgsql: Doc: add a bit to indices.sgml about what is an indexable clause
Doc: add a bit to indices.sgml about what is an indexable clause. We didn't explain this clearly until somewhere deep in the "Extending SQL" chapter, but really it ought to be mentioned in the introductory material too. Discussion: https://postgr.es/m/4097442.1694967...@sss.pgh.pa.us Branch -- REL_16_STABLE Details --- https://git.postgresql.org/pg/commitdiff/8b9d39254816195abb55ab204e39f8fa476aad23 Modified Files -- doc/src/sgml/indices.sgml | 35 ++- 1 file changed, 34 insertions(+), 1 deletion(-)
pgsql: Doc: add a bit to indices.sgml about what is an indexable clause
Doc: add a bit to indices.sgml about what is an indexable clause. We didn't explain this clearly until somewhere deep in the "Extending SQL" chapter, but really it ought to be mentioned in the introductory material too. Discussion: https://postgr.es/m/4097442.1694967...@sss.pgh.pa.us Branch -- REL_12_STABLE Details --- https://git.postgresql.org/pg/commitdiff/499342e81b0fba471889439e47e0c37fe9e62bc0 Modified Files -- doc/src/sgml/indices.sgml | 35 ++- 1 file changed, 34 insertions(+), 1 deletion(-)
pgsql: Doc: add a bit to indices.sgml about what is an indexable clause
Doc: add a bit to indices.sgml about what is an indexable clause. We didn't explain this clearly until somewhere deep in the "Extending SQL" chapter, but really it ought to be mentioned in the introductory material too. Discussion: https://postgr.es/m/4097442.1694967...@sss.pgh.pa.us Branch -- master Details --- https://git.postgresql.org/pg/commitdiff/b7412e293b6b3bf9dd02596d6f6be456a0597d58 Modified Files -- doc/src/sgml/indices.sgml | 35 ++- 1 file changed, 34 insertions(+), 1 deletion(-)
pgsql: Doc: add a bit to indices.sgml about what is an indexable clause
Doc: add a bit to indices.sgml about what is an indexable clause. We didn't explain this clearly until somewhere deep in the "Extending SQL" chapter, but really it ought to be mentioned in the introductory material too. Discussion: https://postgr.es/m/4097442.1694967...@sss.pgh.pa.us Branch -- REL_15_STABLE Details --- https://git.postgresql.org/pg/commitdiff/afc987e196107b0887314838256a885af05b8714 Modified Files -- doc/src/sgml/indices.sgml | 35 ++- 1 file changed, 34 insertions(+), 1 deletion(-)
