Upcoming custom Table Access Methods (TableAM) need benchmarking. Despite
pgbench doesn't have an explicit option for TableAM specification, one can
specify it using PGOPTION environmental variable. The present commit documents
this way to specify TableAM for pgbench.
Discussion: https://postgr.es/m/CAC77N6ih%3DLbhZQXV76grEsaVQkBL464Y2Foqq9o%3Df4UBfEOfEQ%40mail.gmail.com
Author: Michel Pelletier, Alexander Korotkov
Reviewed-by: Justin Pryzby, Mason Sharp, Michael Paquier
Remove meaningless "failures" column from the aggregate logging. It
was just a sum of "serialization failures" and "deadlock failures".
Pointed out by Tom Lane. Patch reviewed by Fabien COELHO.
Discussion: https://postgr.es/m/4183048.1649536705%40sss.pgh.pa.us
This is mostly driven by trying to get rid of line-too-wide
warnings in PDF output; but I think converting to a <variablelist>
makes it more readable anyway.
Discussion: https://postgr.es/m/4183048.1649536705@sss.pgh.pa.us
Whitespace between tags is significant, and in some cases it creates
extra vertical space in man pages. The fix is to remove some newlines
in the markup.
Commit 4a39f87acd changed the aggregated log format. Problem is, now
the explanatory paragraph for the log line in the document is too
long. Also the log format included more optional columns, and it's
harder to parse the log lines. This commit tries to solve the
problems.
- There's no optional log columns anymore. If a column is not
meaningful with provided pgbench option, it will be presented as 0.
- Reorder the log columns so that it's easier to parse them.
- Adjust explanatory paragraph for the log line in the doc.
Discussion: https://postgr.es/m/flat/202203280757.3tu4ovs3petm%40alvherre.pgsql
When serialization or deadlock errors are reported by backend, allow
to retry and continue the benchmarking. For this purpose new options
"--max-tries", "--failures-detailed" and "--verbose-errors" are added.
Transactions with serialization errors or deadlock errors will be
repeated after rollbacks until they complete successfully or reach the
maximum number of tries (specified by the --max-tries option), or the
maximum time of tries (specified by the --latency-limit option).
These options can be specified at the same time. It is not possible to
use an unlimited number of tries (--max-tries=0) without the
--latency-limit option or the --time option. By default the option
--max-tries is set to 1, which means transactions with
serialization/deadlock errors are not retried. If the last try fails,
this transaction will be reported as failed, and the client variables
will be set as they were before the first run of this transaction.
Statistics on retries and failures are printed in the progress,
transaction / aggregation logs and in the end with other results (all
and for each script). Also retries and failures are printed
per-command with average latency by using option
(--report-per-command, -r).
Option --failures-detailed prints group failures by basic types
(serialization failures / deadlock failures).
Option --verbose-errors prints distinct reports on errors and failures
(errors without retrying) by type with detailed information like which
limit for retries was violated and how far it was exceeded for the
serialization/deadlock failures.
Patch originally written by Marina Polyakova then Yugo Nagata
inherited the discussion and heavily modified the patch to make it
commitable.
Authors: Yugo Nagata, Marina Polyakova
Reviewed-by: Fabien Coelho, Tatsuo Ishii, Alvaro Herrera, Kevin Grittner, Andres Freund, Arthur Zakirov, Alexander Korotkov, Teodor Sigaev, Ildus Kurbangaliev
Discussion: https://postgr.es/m/flat/72a0d590d6ba06f242d75c2e641820ec%40postgrespro.ru
This fixes a set of issues that have accumulated over the past months
(or years) in various code areas. Most fixes are related to some recent
additions, as of the development of v15.
Author: Justin Pryzby
Discussion: https://postgr.es/m/20220124030001.GQ23027@telsasoft.com
Previously failures of initial connection and logfile open caused pgbench
to proceed the benchmarking, report the incomplete results and exit with
status 2. It didn't make sense to proceed the benchmarking even when
pgbench could not start as prescribed.
This commit improves pgbench so that early errors that occur when
starting benchmark such as those failures should make pgbench exit
immediately with status 1.
Author: Yugo Nagata
Reviewed-by: Fabien COELHO, Kyotaro Horiguchi, Fujii Masao
Discussion: https://postgr.es/m/TYCPR01MB5870057375ACA8A73099C649F5349@TYCPR01MB5870.jpnprd01.prod.outlook.com
While populating the pgbench_accounts table, plain COPY was
unconditionally used. By changing it to COPY FREEZE, the time for
VACUUM is significantly reduced, thus the total time of "pgbench -i"
is also reduced. This only happens if pgbench runs against PostgreSQL
14 or later because COPY FREEZE in previous versions of PostgreSQL does
not bring the benefit. Also if partitioning is used, COPY FREEZE
cannot be used. In this case plain COPY will be used too.
Author: Tatsuo Ishii
Discussion: https://postgr.es/m/20210308.143907.2014279678657453983.t-ishii@gmail.com
Reviewed-by: Fabien COELHO, Laurenz Albe, Peter Geoghegan, Dean Rasheed
We've accumulated quite a mix of instances of "an SQL" and "a SQL" in the
documents. It would be good to be a bit more consistent with these.
The most recent version of the SQL standard I looked at seems to prefer
"an SQL". That seems like a good lead to follow, so here we change all
instances of "a SQL" to become "an SQL". Most instances correctly use
"an SQL" already, so it also makes sense to use the dominant variation in
order to minimise churn.
Additionally, there were some other abbreviations that needed to be
adjusted. FSM, SSPI, SRF and a few others. Also fix some pronounceable,
abbreviations to use "a" instead of "an". For example, "a SASL" instead
of "an SASL".
Here I've only adjusted the documents and error messages. Many others
still exist in source code comments. Translator hint comments seem to be
the biggest culprit. It currently does not seem worth the churn to change
these.
Discussion: https://postgr.es/m/CAApHDvpML27UqFXnrYO1MJddsKVMQoiZisPvsAGhKE_tsKXquw%40mail.gmail.com
This adds a new function, permute(), that generates pseudorandom
permutations of arbitrary sizes. This can be used to randomly shuffle
a set of values to remove unwanted correlations. For example,
permuting the output from a non-uniform random distribution so that
all the most common values aren't collocated, allowing more realistic
tests to be performed.
Formerly, hash() was recommended for this purpose, but that suffers
from collisions that might alter the distribution, so recommend
permute() for this purpose instead.
Fabien Coelho and Hironobu Suzuki, with additional hacking be me.
Reviewed by Thomas Munro, Alvaro Herrera and Muhammad Usama.
Discussion: https://postgr.es/m/alpine.DEB.2.21.1807280944370.5142@lancre
The point of this restriction is to avoid trying to substitute variables
into timestamp literal values, which may contain strings like '12:34'.
There is a good deal more that should be done to reduce pgbench's
tendency to substitute where it shouldn't. But this is sufficient to
solve the case complained of by Jaime Soler, and it's simple enough
to back-patch.
Back-patch to v11; before commit 9d36a3866, pgbench had a slightly
different definition of what a variable name is, and anyway it seems
unwise to change long-stable branches for this.
Fabien Coelho
Discussion: https://postgr.es/m/alpine.DEB.2.22.394.2006291740420.805678@pseudo
Whitespace between tags is significant, and in some cases it creates
extra vertical space in man pages. The fix is either to remove some
newlines or in some cases to reword slightly to avoid the awkward
markup layout.
This converts the contrib documentation to the new style, and mops up
a couple of function tables that were outside chapter 9 in the main
docs.
A few contrib modules choose not to present their functions in the
standard tabular format. There might be room to rethink those decisions
now that the standard format is more friendly to verbose descriptions.
But I have not undertaken to do that here; I just converted existing
tables.
This option is similar to \gset, except that it is able to store all
results from combined SQL queries into separate variables. If a query
returns multiple rows, the last result is stored and if a query returns
no rows, nothing is stored.
While on it, add a TAP test for \gset to check for a failure when a
query returns multiple rows.
Author: Fabien Coelho
Reviewed-by: Ibrar Ahmed, Michael Paquier
Discussion: https://postgr.es/m/alpine.DEB.2.21.1904081914200.2529@lancre
This addresses a couple of issues in the documentation:
- Description of PG_COLOR was missing for some tools (pg_archivecleanup
and pg_test_fsync), while the other descriptions had grammar mistakes.
- pgbench supports more environment variables: PGUSER, PGHOST and
PGPORT.
- vacuumlo, oid2name and pgbench support coloring (HEAD only)
Author: Michael Paquier
Reviewed-by: Fabien Coelho, Daniel Gustafsson, Juan José Santamaría
Flecha
Discussion: https://postgr.es/m/20200304075418.GJ2593@paquier.xyz
Backpatch-through: 12
This commit allows --init-steps option in pgbench to accept "G" character
meaning server-side data generation as an initialization step.
With "G", only limited queries are sent from pgbench client and
then data is actually generated in the server. This might make
the initialization phase faster if the bandwidth between pgbench client
and the server is low.
Author: Fabien Coelho
Reviewed-by: Anna Endo, Ibrar Ahmed, Fujii Masao
Discussion: https://postgr.es/m/alpine.DEB.2.21.1904061826420.3678@lancre
These new options allow users to partition the pgbench_accounts table by
specifying the number of partitions and partitioning method. The values
allowed for partitioning method are range and hash.
This feature allows users to measure the overhead of partitioning if any.
Author: Fabien COELHO
Reviewed-by: Amit Kapila, Amit Langote, Dilip Kumar, Asif Rehman, and
Alvaro Herrera
Discussion: https://postgr.es/m/alpine.DEB.2.21.1907230826190.7008@lancre
Remove the code that supported zipfian distribution parameters less
than 1.0, as it had undocumented performance hazards, and it's not
clear that the case is useful enough to justify either fixing or
documenting those hazards.
Also, since the code path for parameter > 1.0 could perform badly
for values very close to 1.0, establish a minimum allowed value
of 1.001. This solution seems superior to the previous vague
documentation warning about small values not performing well.
Fabien Coelho, per a gripe from Tomas Vondra
Discussion: https://postgr.es/m/b5e172e9-ad22-48a3-86a3-589afa20e8f7@2ndquadrant.com
Partial revert of commit 6260cc550b, "pgbench: add \cset and \gset
commands".
While \gset is widely considered a useful and necessary tool for user-
defined benchmarks, \cset does not have as much value, and its
implementation was considered "not to be up to project standards"
(though I, Álvaro, can't quite understand exactly how). Therefore,
remove \cset.
Author: Fabien Coelho
Discussion: https://postgr.es/m/alpine.DEB.2.21.1903230716030.18811@lancre
Discussion: https://postgr.es/m/201901101900.mv7zduch6sad@alvherre.pgsql
pgbench's arbitrary limit of 10 arguments for SQL statements or
metacommands is far too low. Increase it to 256.
This results in a very modest increase in memory usage, not enough to
worry about.
The maximum includes the SQL statement or metacommand. This is reflected
in the comments and revised TAP tests.
Simon Riggs and Dagfinn Ilmari Mannsåker with some light editing by me.
Reviewed by: David Rowley and Fabien Coelho
Discussion: https://postgr.es/m/CANP8+jJiMJOAf-dLoHuR-8GENiK+eHTY=Omw38Qx7j2g0NDTXA@mail.gmail.com
The pgbench regression test supposed that srandom() with a specific value
would result in deterministic output from random(), as required by POSIX.
It emerges however that OpenBSD is too smart to be constrained by mere
standards, so their random() emits nondeterministic output anyway.
While a workaround does exist, what seems like a better fix is to stop
relying on the platform's srandom()/random() altogether, so that what
you get from --random-seed=N is not merely deterministic but platform
independent. Hence, use a separate pg_jrand48() random sequence in
place of random().
Also adjust the regression test case that's supposed to detect
nondeterminism so that it's more likely to detect it; the original
choice of random_zipfian parameter tended to produce the same output
all the time even if the underlying behavior wasn't deterministic.
In passing, improve pgbench's docs about random_zipfian().
Back-patch to v11 where this code was introduced.
Fabien Coelho and Tom Lane
Discussion: https://postgr.es/m/4615.1547792324@sss.pgh.pa.us
These commands allow assignment of values produced by queries to pgbench
variables, where they can be used by further commands. \gset terminates
a command sequence (just like a bare semicolon); \cset separates
multiple queries in a compound command, like an escaped semicolon (\;).
A prefix can be provided to the \-command and is prepended to the name
of each output column to produce the final variable name.
This feature allows pgbench scripts to react meaningfully to the actual
database contents, allowing more powerful benchmarks to be written.
Authors: Fabien Coelho, Álvaro Herrera
Reviewed-by: Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>
Reviewed-by: Stephen Frost <sfrost@snowman.net>
Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Tatsuo Ishii <ishii@sraoss.co.jp>
Reviewed-by: Rafia Sabih <rafia.sabih@enterprisedb.com>
Discussion: https://postgr.es/m/alpine.DEB.2.20.1607091005330.3412@sto
When an error occurs during a benchmark run, exit with a nonzero exit
code and write a message at the end. Previously, it would just print
the error message when it happened but then proceed to print the run
summary normally and exit with status 0. To still allow
distinguishing setup from run-time errors, we use exit status 2 for
the new state, whereas existing errors during pgbench initialization
use exit status 1.
Reviewed-by: Fabien COELHO <coelho@cri.ensmp.fr>
