The previous coding first generated a uniform random value between 0.0 and 1.0, then converted that to an integer between 1 and 10000, and divided that again by 10000. Those conversions are unnecessary; we can use the double value that pg_erand48() returns directly. While we're at it, put the logic into a helper function, getPoissonRand(). The largest delay generated by the old coding was about 9.2 times the average, because of the way the uniformly distributed value used for the calculation was truncated to 1/10000 granularity. The new coding doesn't have such clamping. With my laptop's DBL_MIN value, the maximum delay with the new coding is about 700x the average. That seems acceptable - any reasonable pgbench session should last long enough to average that out. Backpatch to 9.4. |
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.. | ||
adminpack | ||
auth_delay | ||
auto_explain | ||
btree_gin | ||
btree_gist | ||
chkpass | ||
citext | ||
cube | ||
dblink | ||
dict_int | ||
dict_xsyn | ||
dummy_seclabel | ||
earthdistance | ||
file_fdw | ||
fuzzystrmatch | ||
hstore | ||
intagg | ||
intarray | ||
isn | ||
lo | ||
ltree | ||
oid2name | ||
pageinspect | ||
passwordcheck | ||
pg_archivecleanup | ||
pg_buffercache | ||
pg_freespacemap | ||
pg_prewarm | ||
pg_standby | ||
pg_stat_statements | ||
pg_test_fsync | ||
pg_test_timing | ||
pg_trgm | ||
pg_upgrade | ||
pg_upgrade_support | ||
pg_xlogdump | ||
pgbench | ||
pgcrypto | ||
pgrowlocks | ||
pgstattuple | ||
postgres_fdw | ||
seg | ||
sepgsql | ||
spi | ||
sslinfo | ||
start-scripts | ||
tablefunc | ||
tcn | ||
test_decoding | ||
test_parser | ||
test_shm_mq | ||
tsearch2 | ||
unaccent | ||
uuid-ossp | ||
vacuumlo | ||
worker_spi | ||
xml2 | ||
Makefile | ||
README | ||
contrib-global.mk |
README
The PostgreSQL contrib tree --------------------------- This subtree contains porting tools, analysis utilities, and plug-in features that are not part of the core PostgreSQL system, mainly because they address a limited audience or are too experimental to be part of the main source tree. This does not preclude their usefulness. User documentation for each module appears in the main SGML documentation. When building from the source distribution, these modules are not built automatically, unless you build the "world" target. You can also build and install them all by running "make all" and "make install" in this directory; or to build and install just one selected module, do the same in that module's subdirectory. Some directories supply new user-defined functions, operators, or types. To make use of one of these modules, after you have installed the code you need to register the new SQL objects in the database system by executing a CREATE EXTENSION command. In a fresh database, you can simply do CREATE EXTENSION module_name; See the PostgreSQL documentation for more information about this procedure.