This will write the received transaction log into a file called
pg_wal.tar(.gz) next to the other tarfiles instead of writing it to
base.tar. When using fetch mode, the transaction log is still written to
base.tar like before, and when used against a pre-10 server, the file
is named pg_xlog.tar.
To do this, implement a new concept of a "walmethod", which is
responsible for writing the WAL. Two implementations exist, one that
writes to a plain directory (which is also used by pg_receivexlog) and
one that writes to a tar file with optional compression.
Reviewed by Michael Paquier
"xlog" is not a particularly clear abbreviation for "write-ahead log",
and it sometimes confuses users into believe that the contents of the
"pg_xlog" directory are not critical data, leading to unpleasant
consequences. So, rename the directory to "pg_wal".
This patch modifies pg_upgrade and pg_basebackup to understand both
the old and new directory layouts; the former is necessary given the
purpose of the tool, while the latter merely avoids an unnecessary
backward-compatibility break.
We may wish to consider renaming other programs, switches, and
functions which still use the old "xlog" naming to also refer to
"wal". However, that's still under discussion, so let's do just this
much for now.
Discussion: CAB7nPqTeC-8+zux8_-4ZD46V7YPwooeFxgndfsq5Rg8ibLVm1A@mail.gmail.com
Michael Paquier
--noclean and --nosync were the only options spelled without a hyphen,
so change this for consistency with other options. The options in
pg_basebackup have not been in a release, so we just rename them. For
initdb, we retain the old variants.
Vik Fearing and me
Several places weren't careful about fsyncing in the way. See 1d4a0ab1
and 606e0f98 for details about required fsyncs.
This adds a couple of functions in src/common/ that have an equivalent
in the backend: durable_rename(), fsync_parent_path()
From: Michael Paquier <michael.paquier@gmail.com>
<sys/select.h> is required by POSIX.1-2001 to get the prototype of
select(2), but nearly no systems enforce that because older standards
let you get away with including some other headers. Recent OpenBSD
hacking has removed that frail touch of friendliness, however, which
broke some compiles; fix all the way back to 9.1 by adding the required
standard. Only vacuumdb.c was reported to fail, but it seems easier to
fix the whole lot in a fell swoop.
Per bug #14334 by Sean Farrell.
Like initdb, clean up created data and xlog directories, unless the new
-n/--noclean option is specified.
Tablespace directories are not cleaned up, but a message is written
about that.
Reviewed-by: Masahiko Sawada <sawada.mshk@gmail.com>
It is redundant with appendConnStrVal(), which became an extern function
in commit 41f18f021a. This changes the
handling of out-of-memory and of certain inputs for which quoting is
optional, but pg_basebackup has no need for unusual treatment thereof.
The help message for pg_basebackup specifies that the numbers 0 through 9
are accepted as valid values of -Z option. But, previously -Z 0 was rejected
as an invalid compression level.
Per discussion, it's better to make pg_basebackup treat 0 as valid
compression level meaning no compression, like pg_dump.
Back-patch to all supported versions.
Reported-By: Jeff Janes
Reviewed-By: Amit Kapila
Discussion: CAMkU=1x+GwjSayc57v6w87ij6iRGFWt=hVfM0B64b1_bPVKRqg@mail.gmail.com
Adjust the way we detect the locale. As a result the minumum Windows
version supported by VS2015 and later is Windows Vista. Add some tweaks
to remove new compiler warnings. Remove documentation references to the
now obsolete msysGit.
Michael Paquier, somewhat edited by me, reviewed by Christian Ullrich.
Backpatch to 9.5
Much cruft had accumulated over time with a large number of parameters
passed down between functions very deep. With this refactoring, instead
introduce a StreamCtl structure that holds the parameters, and pass around
a pointer to this structure instead. This makes it much easier to add or
remove fields that are needed deeper down in the implementation without
having to modify every function header in the file.
Patch by me after much nagging from Andres
Reviewed by Craig Ringer and Daniel Gustafsson
The POSIX standard for tar headers requires archive member sizes to be
printed in octal with at most 11 digits, limiting the representable file
size to 8GB. However, GNU tar and apparently most other modern tars
support a convention in which oversized values can be stored in base-256,
allowing any practical file to be a tar member. Adopt this convention
to remove two limitations:
* pg_dump with -Ft output format failed if the contents of any one table
exceeded 8GB.
* pg_basebackup failed if the data directory contained any file exceeding
8GB. (This would be a fatal problem for installations configured with a
table segment size of 8GB or more, and it has also been seen to fail when
large core dump files exist in the data directory.)
File sizes under 8GB are still printed in octal, so that no compatibility
issues are created except in cases that would have failed entirely before.
In addition, this patch fixes several bugs in the same area:
* In 9.3 and later, we'd defined tarCreateHeader's file-size argument as
size_t, which meant that on 32-bit machines it would write a corrupt tar
header for file sizes between 4GB and 8GB, even though no error was raised.
This broke both "pg_dump -Ft" and pg_basebackup for such cases.
* pg_restore from a tar archive would fail on tables of size between 4GB
and 8GB, on machines where either "size_t" or "unsigned long" is 32 bits.
This happened even with an archive file not affected by the previous bug.
* pg_basebackup would fail if there were files of size between 4GB and 8GB,
even on 64-bit machines.
* In 9.3 and later, "pg_basebackup -Ft" failed entirely, for any file size,
on 64-bit big-endian machines.
In view of these potential data-loss bugs, back-patch to all supported
branches, even though removal of the documented 8GB limit might otherwise
be considered a new feature rather than a bug fix.
This option specifies a replication slot for WAL streaming (-X stream),
so that there can be continuous replication slot use between WAL
streaming during the base backup and the start of regular streaming
replication.
Reviewed-by: Michael Paquier <michael.paquier@gmail.com>
Patch by David Rowley. Backpatch to 9.5, as some of the calls were new in
9.5, and keeping the code in sync with master makes future backpatching
easier.
Windows can't reliably restore symbolic links from a tar format, so
instead during backup start we create a tablespace_map file, which is
used by the restoring postgres to create the correct links in pg_tblspc.
The backup protocol also now has an option to request this file to be
included in the backup stream, and this is used by pg_basebackup when
operating in tar mode.
This is done on all platforms, not just Windows.
This means that pg_basebackup will not not work in tar mode against 9.4
and older servers, as this protocol option isn't implemented there.
Amit Kapila, reviewed by Dilip Kumar, with a little editing from me.
WAL (and timeline history) files created by pg_basebackup did not
maintain the new base backup's archive status. That's currently not a
problem if the new node is used as a standby - but if that node is
promoted all still existing files can get archived again. With a high
wal_keep_segment settings that can happen a significant time later -
which is quite confusing.
Change both the backend (for the -x/-X fetch case) and pg_basebackup
(for -X stream) itself to always mark WAL/timeline files included in
the base backup as .done. That's in line with walreceiver.c doing so.
The verbosity of the pg_basebackup changes show pretty clearly that it
needs some refactoring, but that'd result in not be backpatchable
changes.
Backpatch to 9.1 where pg_basebackup was introduced.
Discussion: 20141205002854.GE21964@awork2.anarazel.de
Previously pg_receivexlog flushed WAL data only when WAL file was switched.
Then 3dad73e added -F option to pg_receivexlog so that users could control
how frequently sync commands were issued to WAL files. It also allowed users
to make pg_receivexlog flush WAL data immediately after writing by
specifying 0 in -F option. However feedback messages were not sent back
immediately even after a flush location was updated. So even if WAL data
was flushed in real time, the server could not see that for a while.
This commit removes -F option from and adds --synchronous to pg_receivexlog.
If --synchronous is specified, like the standby's wal receiver, pg_receivexlog
flushes WAL data as soon as there is WAL data which has not been flushed yet.
Then it sends back the feedback message identifying the latest flush location
to the server. This option is useful to make pg_receivexlog behave as sync
standby by using replication slot, for example.
Original patch by Furuya Osamu, heavily rewritten by me.
Reviewed by Heikki Linnakangas, Alvaro Herrera and Sawada Masahiko.
Move some more code to manage replication connection command to
streamutil.c. A later patch will introduce replication slot via
pg_receivexlog and this avoid duplicating relevant code between
pg_receivexlog and pg_recvlogical.
Author: Michael Paquier, with some editing by me.
Previously, we would first create the symlinks the way they are in the
original system, and at the end replace them with the mapped symlinks.
That never really made much sense, so now we create the symlink pointing
to the correct location to begin with, so that there's no need to fix
them at the end.
The old coding didn't work correctly on Windows, because Windows junction
points look more like directories than files, and ought to be removed with
rmdir rather than unlink. Also, it incorrectly used "%d" rather than "%u"
to print an Oid, but that's gone now.
Report and patch by Amit Kapila, with minor changes by me. Reviewed by
MauMau. Backpatch to 9.4, where the --tablespace feature was added.
This reverts commit 083d29c65b.
The commit changed the code so that it causes an errors when
IDENTIFY_SYSTEM returns three columns. But which prevents us
from using the replication-related utilities against the server
with older version. This is not what we want. For that
compatibility, we allow the utilities to receive three columns
as the result of IDENTIFY_SYSTEM eventhough it actually returns
four columns in 9.4 or later.
Pointed out by Andres Freund.
5a991ef869 added new column into
the result of IDENTIFY_SYSTEM command. But it was not reflected into
several codes checking that result. Specifically though the number of
columns in the result was increased to 4, it was still compared with 3
in some replication codes.
Back-patch to 9.4 where the number of columns in IDENTIFY_SYSTEM
result was increased.
Report from Michael Paquier
This allows us to specify the maximum time to issue fsync to ensure
the received WAL file is safely flushed to disk. Without this,
pg_receivexlog always flushes WAL file only when it's closed and
which can cause WAL data to be lost at the event of a crash.
Furuya Osamu, heavily modified by me.
In order for this to work, walsenders need the optional ability to
connect to a database, so the "replication" keyword now allows true
or false, for backward-compatibility, and the new value "database"
(which causes the "dbname" parameter to be respected).
walsender needs to loop not only when idle but also when sending
decoded data to the user and when waiting for more xlog data to decode.
This means that there are now three separate loops inside walsender.c;
although some refactoring has been done here, this is still a bit ugly.
Andres Freund, with contributions from Álvaro Herrera, and further
review by me.
A new MAX_RATE option allows imposing a limit to the network transfer
rate from the server side. This is useful to limit the stress that
taking a base backup has on the server.
pg_basebackup is now able to specify a value to the server, too.
Author: Antonin Houska
Patch reviewed by Stefan Radomski, Andres Freund, Zoltán Böszörményi,
Fujii Masao, and Álvaro Herrera.
Tablespaces can be relocated in plain backup mode by specifying one or
more -T olddir=newdir options.
Author: Steeve Lennmark <steevel@handeldsbanken.se>
Reviewed-by: Peter Eisentraut <peter_e@gmx.net>
Coverity identified a number of places in which it couldn't prove that a
string being copied into a fixed-size buffer would fit. We believe that
most, perhaps all of these are in fact safe, or are copying data that is
coming from a trusted source so that any overrun is not really a security
issue. Nonetheless it seems prudent to forestall any risk by using
strlcpy() and similar functions.
Fixes by Peter Eisentraut and Jozef Mlich based on Coverity reports.
In addition, fix a potential null-pointer-dereference crash in
contrib/chkpass. The crypt(3) function is defined to return NULL on
failure, but chkpass.c didn't check for that before using the result.
The main practical case in which this could be an issue is if libc is
configured to refuse to execute unapproved hashing algorithms (e.g.,
"FIPS mode"). This ideally should've been a separate commit, but
since it touches code adjacent to one of the buffer overrun changes,
I included it in this commit to avoid last-minute merge issues.
This issue was reported by Honza Horak.
Security: CVE-2014-0065 for buffer overruns, CVE-2014-0066 for crypt()
If an error occurs in the foreground (backup) process of pg_basebackup,
and we exit in a controlled way, the background process (streaming
xlog process) would stay around and keep streaming.
This prevents pg_basebackup from generating excessive output when
dumping large clusters. The status is now updated once / second,
still making it possible to see that there is progress happening,
but limiting the total bandwidth.
Mika Eloranta, reviewed by Sawada Masahiko and Oskari Saarenmaa
When using verbose mode for pg_basebackup, in tar format sent to
stdout, we'd print an unitialized buffer as the filename.
Reported by Pontus Lundkvist
In pg_basebackup.c:reached_end_position(), we're reading from an
internal pipe with our own background process but we're possibly
reading more bytes than will actually fit into our buffer due to
an off-by-one error. As we're reading from an internal pipe
there's no real risk here, but it's good form to not depend on
such convenient arrangements.
Bug spotted by the Coverity scanner.
Back-patch to 9.2 where this showed up.
In the primary_conninfo line that "pg_basebackup -R" generates, single
quotes in parameter values need to be escaped into \\'; the libpq parser
requires the quotes to be escaped into \', and recovery.conf parser requires
the \ to be escaped into \\.
Also, don't quote parameter values unnecessarily, to make the connection
string prettier. Most options in a libpq connection string don't need
quoting.
Reported by Hari Babu, closer analysis by Zoltan Boszormenyi, although I
didn't use his patch.
A new 'starttli' field was added to the response of BASE_BACKUP command.
Make pg_basebackup tolerate the case that it's missing, so that it still
works with older servers.
Add an explicit check for the server version, so that you get a nicer error
message if you try to use it with a pre-9.1 server.
The streaming protocol message format changed in 9.3, so -X stream still won't
work with pre-9.3 servers. I added a version check to ReceiveXLogStream()
earlier, but write that slightly differently, so that in 9.4, it will still
work with a 9.3 server. (In 9.4, the error message needs to be adjusted to
"9.3 or above", though). Also, if the version check fails, don't retry.
Without this, there's no way to pass arbitrary libpq connection parameters
to these applications. It's a bit strange that the option is called
-d/--dbname, when in fact you can *not* pass a database name in it, but it's
consistent with other client applications where a connection string is also
passed using -d.
Original patch by Amit Kapila, heavily modified by me.
This mirrors the changes done earlier to the server in standby mode. When
receivelog reaches the end of a timeline, as reported by the server, it
fetches the timeline history file of the next timeline, and restarts
streaming from the new timeline by issuing a new START_STREAMING command.
When pg_receivexlog crosses a timeline, it leaves the .partial suffix on the
last segment on the old timeline. This helps you to tell apart a partial
segment left in the directory because of a timeline switch, and a completed
segment. If you just follow a single server, it won't make a difference, but
it can be significant in more complicated scenarios where new WAL is still
generated on the old timeline.
This includes two small changes to the streaming replication protocol:
First, when you reach the end of timeline while streaming, the server now
sends the TLI of the next timeline in the server's history to the client.
pg_receivexlog uses that as the next timeline, so that it doesn't need to
parse the timeline history file like a standby server does. Second, when
BASE_BACKUP command sends the begin and end WAL positions, it now also sends
the timeline IDs corresponding the positions.
When truncating at the end, like before, the output would often end up
just showing the path instead of the filename.
Also increase the length of the filename by 5, which still keeps us at
less than 80 characters in most outputs.
Adds commandline option -R to pg_basebackup that creates a recovery.conf which
enables standby mode using the same parameters that pg_basebackup used to
connect to the master, and writes it into the output directory (or injects it
in the tar file when tar format is used).
Zoltan Boszormenyi, modified by Magnus Hagander, reviewed by Amit Kapila & Fujii Masao
We had a number of variants on the theme of "malloc or die", with the
majority named like "pg_malloc", but by no means all. Standardize on the
names pg_malloc, pg_malloc0, pg_realloc, pg_strdup. Get rid of pg_calloc
entirely in favor of using pg_malloc0.
This is an essentially cosmetic change, so no back-patch. (I did find
a couple of places where psql and pg_dump were using plain malloc or
strdup instead of the pg_ versions, but they don't look significant
enough to bother back-patching.)
The most user-visible part of this is to change the long options
--statusint and --noloop to --status-interval and --no-loop,
respectively, per discussion.
Also, consistently enclose file names in double quotes, per our
conventions; and consistently use the term "transaction log file" to
talk about WAL segments. (Someday we may need to go over this
terminology and make it consistent across the whole source code.)
Finally, reflow the code to better fit in 80 columns, and have pgindent
fix it up some more.
This simplifies code that needs to do arithmetic on XLogRecPtrs.
To avoid changing on-disk format of data pages, the LSN on data pages is
still stored in the old format. That should keep pg_upgrade happy. However,
we have XLogRecPtrs embedded in the control file, and in the structs that
are sent over the replication protocol, so this changes breaks compatibility
of pg_basebackup and server. I didn't do anything about this in this patch,
per discussion on -hackers, the right thing to do would to be to change the
replication protocol to be architecture-independent, so that you could use
a newer version of pg_receivexlog, for example, against an older server
version.
Before, some places didn't document the short options (-? and -V),
some documented both, some documented nothing, and they were listed in
various orders. Now this is hopefully more consistent and complete.
To replace it, add -X/--xlog-method that allows the specification
of fetch or stream.
Do this to avoid unnecessary backwards-incompatiblity. Spotted and
suggested by Peter Eisentraut.
Since the replication protocol deals with TimestampTz, we need to
care for the floating point case as well in the frontend tools.
Fujii Masao, with changes from Magnus Hagander
When backing up from a standby server, the backup process
will not automatically switch xlog segment. So we must
accept a partially transferred xlog file in this case, but
rename it into position anyway.
In passing, merge the two callbacks for segment end and
stop stream into a single callback, since their implementations
were close to identical, and rename this callback to
reflect that it stops streaming rather than continues it.
Patch by Magnus Hagander, review by Fujii Masao
gzFile is already a pointer, so code like
gzFile *handle = gzopen(...)
is wrong.
This used to pass silently because gzFile used to be defined as void*,
and you can assign a void* to a void**. But somewhere between zlib
versions 1.2.3.4 and 1.2.6, the definition of gzFile was changed to
struct gzFile_s *, and with that new definition this usage causes
compiler warnings.
So remove all those extra pointer decorations.
There is a related issue in pg_backup_archiver.h, where
FILE *FH; /* General purpose file handle */
is used throughout pg_dump as sometimes a real FILE* and sometimes a
gzFile handle, which also causes warnings now. This is not yet fixed
here, because it might need more code restructuring.
Add option for parallel streaming of the transaction log while a
base backup is running, to get the logfiles before the server has
removed them.
Also add a tool called pg_receivexlog, which streams the transaction
log into files, creating a log archive without having to wait for
segments to complete, thus decreasing the window of data loss without
having to waste space using archive_timeout. This works best in
combination with archive_command - suggested usage docs etc coming later.
When streaming including WAL, the size estimate will always be incorrect,
since we don't know how much WAL is included. To make sure the output doesn't
look completely unreasonable, this patch increases the total size whenever we
go past the estimate, to make sure we never go above 100%.
The short-form -z switch didn't work, for lack of telling getopt_long
about it; and even if specified long-form, it failed to do anything,
because the various tests elsewhere in the file would take
Z_DEFAULT_COMPRESSION (which is -1) as meaning "don't compress".
Per bug #6060 from Shigehiro Honda, though I editorialized on his patch
a bit.
This code was accidentally part of the patch, it's only
needed for the code that's for 9.2. Not needing the timeline
also removes the need to call IDENTIFY_SYSTEM.
Noted by Peter E.
Add the current xlog insert location to the response of
IDENTIFY_SYSTEM, and adds result sets containing start
and stop location of backups to BASE_BACKUP responses.
When included, this makes the base backup a complete working
"clone" of the initial database, ready to have a postmaster
started against it without the need to set up any log archiving
or similar.
Magnus Hagander, reviewed by Fujii Masao and Heikki Linnakangas
The target of sscanf with a %o format had better be of integer width,
but "mode_t" conceivably isn't that. Another compiler warning seen
only on some platforms; this one I think is potentially a real bug
and not just a warning.
This tool makes it possible to do the pg_start_backup/
copy files/pg_stop_backup step in a single command.
There are still some steps to be done before this is a
complete backup solution, such as the ability to stream
the required WAL logs, but it's still usable, and
could do with some buildfarm coverage.
In passing, make the checkpoint request optionally
fast instead of hardcoding it.
Magnus Hagander, reviewed by Fujii Masao and Dimitri Fontaine
Magnus Hagander
Robert Haas
Peter Eisentraut
Alvaro Herrera
Noah Misch
Fujii Masao
Andrew Dunstan
Bruce Momjian
Tom Lane
Heikki Linnakangas
Andres Freund
Stephen Frost
Greg Stark