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Commit c726afa2 authored by Konstantin Osipov's avatar Konstantin Osipov
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User guide: extend the language reference. 

Extend language-reference.xml.
Minor edits of salloc.m.
parent ee57c04c
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core/salloc.m
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View file @ c726afa2
......@@ -191,7 +191,7 @@ format_slab(struct slab_class *class, struct slab *slab)
}
static bool
full_formated(struct slab *slab)
fully_formatted(struct slab *slab)
{
return slab->brk + slab->class->item_size >= (void *)slab + SLAB_SIZE;
}
......@@ -284,7 +284,7 @@ salloc(size_t size)
VALGRIND_MAKE_MEM_UNDEFINED(item, sizeof(void *));
}
if (full_formated(slab) && slab->free == NULL)
if (fully_formatted(slab) && slab->free == NULL)
TAILQ_REMOVE(&class->free_slabs, slab, class_free_link);
slab->used += class->item_size + sizeof(red_zone);
......@@ -302,7 +302,7 @@ sfree(void *ptr)
struct slab_class *class = slab->class;
struct slab_item *item = ptr;
if (full_formated(slab) && slab->free == NULL)
if (fully_formatted(slab) && slab->free == NULL)
TAILQ_INSERT_TAIL(&class->free_slabs, slab, class_free_link);
assert(valid_item(slab, item));
......
doc/user/language-reference.xml
+ 139
− 28
View file @ c726afa2
......@@ -144,34 +144,145 @@
administrative console. A reference description also follows
below:</para>
<para><emphasis xml:id="reload-configuration" xreflabel="RELOAD CONFIGURATION" role="tntadmin">reload
configuration</emphasis> Re-read the configuration file. If the
file contains changes to dynamic parameters, update the runtime
settings. If configuration syntax is incorrect, or a read-only parameter is changed, produce an error and do nothing.</para>
<para><emphasis xml:id="show-configuration" xreflabel="SHOW CONFIGURATION" role="tntadmin">show configuration</emphasis> Show the current settings. Displays all
settings, including those that have default values and thus are
not necessarily present in the configuration file.</para>
<para><emphasis xml:id="save-snapshot" xreflabel="SAVE SNAPSHOT"
role="tntadmin">save snaspshot</emphasis>
Take a snapshot of all data and store it in
<filename><olink targetptr="snap_dir"/>/&lt;latest-lsn&gt;.snap</filename>.
To take a snapshot, Tarantool forks and quickly
<function>munmap(2)</function>s all
memory except one that stores tuples. Since all modern operating
systems support virtual memory copy-on-write, this effectively
creates a consistent snapshot of all tuples in the child
process, which is then written to disk tuple by tuple. Since a
snapshot is written
sequentially, you can expect a very high write performance
(averaging to 70MB/second on modern disks), which means an
average database instance gets saved in a matter of minutes.
Note, that as long as there are any changes to the parent
memory through concurrent updates, there are going to be page
splits, and therefore you need to have some extra free memory
to run this command. 15%-30% of <olink
targetptr="slab_alloc_arena"/> is, on average, sufficient.
</para>
<variablelist>
<varlistentry>
<term xml:id="save-snapshot" xreflabel="SAVE SNAPSHOT">
<emphasis role="tntadmin">save snapshot</emphasis>
</term>
<listitem><para>
Take a snapshot of all data and store it in
<filename><olink
targetptr="snap_dir"/>/&lt;latest-lsn&gt;.snap</filename>.
To take a snapshot, Tarantool forks and quickly
<function>munmap(2)</function>s all memory except one that
stores tuples. Since all modern operating systems support
virtual memory copy-on-write, this effectively creates a
consistent snapshot of all tuples in the child process,
which is then written to disk tuple by tuple. Since a
snapshot is written sequentially, you can expect a very
high write performance (averaging to 70MB/second on modern
disks), which means an average database instance gets
saved in a matter of minutes. Note, that as long as there
are any changes to the parent memory through concurrent
updates, there are going to be page splits, and therefore
you need to have some extra free memory to run this
command. 15%-30% of <olink targetptr="slab_alloc_arena"/>
is, on average, sufficient.
</para></listitem>
</varlistentry>
<varlistentry>
<term xml:id="reload-configuration" xreflabel="RELOAD CONFIGURATION">
<emphasis role="tntadmin">reload configuration</emphasis>
</term>
<listitem><para>
Re-read the configuration file. If the file contains
changes to dynamic parameters, update the runtime
settings. If configuration syntax is incorrect, or a
read-only parameter is changed, produce an error and do
nothing.
</para></listitem>
</varlistentry>
<varlistentry>
<term xml:id="show-configuration" xreflabel="SHOW CONFIGURATION">
<emphasis role="tntadmin">show configuration</emphasis>
</term>
<listitem><para>
Show the current settings. Displays all settings,
including those that have default values and thus are not
necessarily present in the configuration file.
</para></listitem>
</varlistentry>
<varlistentry>
<term xml:id="show-info" xreflabel="SHOW INFO">
<emphasis role="tntadmin">show info</emphasis>
</term>
<listitem><para>
<programlisting>
tarantool> show info
---
info:
version: "1.4.0-30-ge500b95"
uptime: 441524
pid: 16180
wal_writer_pid: 16182
lsn: 15481913304
recovery_lag: 0.000
recovery_last_update: 1306964594.980
status: primary
</programlisting>
</para></listitem>
</varlistentry>
<varlistentry>
<term xml:id="show-stat" xreflabel="SHOW STAT">
<emphasis role="tntadmin">show stat</emphasis>
</term>
<listitem><para>
<programlisting>
tarantool> show stat
---
statistics:
INSERT: { rps: 139 , total: 48207694 }
SELECT_LIMIT: { rps: 0 , total: 0 }
SELECT: { rps: 1246 , total: 388322317 }
UPDATE_FIELDS: { rps: 1874 , total: 743350520 }
DELETE: { rps: 147 , total: 48902544 }
</programlisting>
</para></listitem>
</varlistentry>
<varlistentry>
<term xml:id="show-slab" xreflabel="SHOW SLAB">
<emphasis role="tntadmin">show slab</emphasis>
</term>
<listitem><para>
Show the statistics of slab allocator. The slab allocator
is the main allocator used to store tuples. This can be
used to monitor the total memory use and memory
fragmentation.
</para></listitem>
</varlistentry>
<varlistentry>
<term xml:id="show-palloc" xreflabel="SHOW PALLOC">
<emphasis role="tntadmin">show palloc</emphasis>
</term>
<listitem><para>
A pool allocator is used for temporary memory, when
serving client requests. Every fiber has an own
pool. Shows the current state of pools of all fibers.
</para></listitem>
</varlistentry>
<varlistentry>
<term xml:id="save-coredump" xreflabel="SAVE COREDUMP">
<emphasis role="tntadmin">SAVE COREDUMP</emphasis>
</term>
<listitem><para>
Fork and dump a core. Since Tarantool stores all tuples
in memory, it can take some time. Mainly useful for
debugging.
</para></listitem>
</varlistentry>
<varlistentry>
<term xml:id="show-fiber" xreflabel="SHOW FIBER">
<emphasis role="tntadmin">show fiber</emphasis>
</term>
<listitem><para>
Show all running fibers, with their stack.
Mainly useful for debugging.
</para></listitem>
</varlistentry>
</variablelist>
</section>
</chapter>
......
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