Oracle 5.0, Reference Manual

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Getting
memcached
Statistics
1387
Statistic Description
outofmemory
The number of items for this slab class that have triggered an out
of memory error (only value when the
-M
command line option is
in effect).
tailrepairs
Number of times the entries for a particular ID need repairing
Item level statistics can be used to determine how many items are stored within a given slab and their
freshness and recycle rate. You can use this to help identify whether there are certain slab classes that
are triggering a much larger number of evictions that others.
15.6.4.4.
memcached
Size Statistics
To get size statistics, use the
stats sizes
command, or the API equivalent.
The size statistics provide information about the sizes and number of items of each size within the
cache. The information is returned as two columns, the first column is the size of the item (rounded up
to the nearest 32 byte boundary), and the second column is the count of the number of items of that
size within the cache:
96 35
128 38
160 807
192 804
224 410
256 222
288 83
320 39
352 53
384 33
416 64
448 51
480 30
512 54
544 39
576 10065
Caution
Running this statistic locks up your cache as each item is read from the cache
and its size calculated. On a large cache, this may take some time and prevent
any set or get operations until the process completes.
The item size statistics are useful only to determine the sizes of the objects you are storing. Since the
actual memory allocation is relevant only in terms of the chunk size and page size, the information is
only useful during a careful debugging or diagnostic session.
15.6.4.5.
memcached
Detail Statistics
For
memcached
1.3.x and higher, you can enable and obtain detailed statistics about the get, set,
and del operations on theindividual keys stored in the cache, and determine whether the attempts hit
(found) a particular key. These operations are only recorded while the detailed stats analysis is turned
on.
To enable detailed statistics, you must send the
stats detail on
command to the
memcached
server:
$ telnet localhost 11211
Trying 127.0.0.1...
Connected to tiger.
Escape character is '^]'. stats detail on
OK
Individual statistics are recorded for every
get
,
set
and
del
operation on a key, including keys that
are not currently stored in the server. For example, if an attempt is made to obtain the value of key