Oracle 5.0 Reference Manual page 1405

A large number of
with information. The number should, over time, decrease in comparison to the number of cache
get_hits. If, however, you have a large number of cache misses compared to cache hits after an
extended period of execution, it may be an indication that the size of the cache is too small and you
either need to increase the total memory size, or increase the number of the
improve the hit ratio.
A large number of
is a sign that your cache is too small to hold the amount of information that you regularly want to keep
cached. Instead of items being retained in the cache, items are being evicted to make way for new
items keeping the turnover of items in the cache high, reducing the efficiency of the cache.
15.6.4.2.
memcached
To get the
slabs
The slab statistics provide you with information about the slabs that have created and allocated for
storing information within the cache. You get information both on each individual slab-class and total
statistics for the whole slab.
STAT 1:chunk_size 104
STAT 1:chunks_per_page 10082
STAT 1:total_pages 1
STAT 1:total_chunks 10082
STAT 1:used_chunks 10081
STAT 1:free_chunks 1
STAT 1:free_chunks_end 10079
STAT 9:chunk_size 696
STAT 9:chunks_per_page 1506
STAT 9:total_pages 63
STAT 9:total_chunks 94878
STAT 9:used_chunks 94878
STAT 9:free_chunks 0
STAT 9:free_chunks_end 0
STAT active_slabs 2
STAT total_malloced 67083616
END
Individual stats for each slab class are prefixed with the slab ID. A unique ID is given to each allocated
slab from the smallest size up to the largest. The prefix number indicates the slab class number in
relation to the calculated chunk from the specified growth factor. Hence in the example, 1 is the first
chunk size and 9 is the 9th chunk allocated size.
The parameters returned for each chunk size and a description of each parameter are provided in the
following table.
Statistic
chunk_size
chunks_per_page
total_pages
total_chunks
used_chunks
free_chunks
free_chunks_end
get_hits
cmd_set
delete_hits
incr_hits
Getting
memcached
may just be an indication that the cache is still being populated
get_misses
from the cache, particularly in comparison to the number of items stored
evictions
Slabs Statistics
statistics, use the
stats slabs
Description
Space allocated to each chunk within this slab class.
Number of chunks within a single page for this slab class.
Number of pages allocated to this slab class.
Number of chunks allocated to the slab class.
Number of chunks allocated to an item..
Number of chunks not yet allocated to items.
Number of free chunks at the end of the last allocated page.
Number of get hits to this chunk
Number of set commands on this chunk
Number of delete hits to this chunk
Number of increment hits to this chunk
Statistics
command, or the API equivalent.
1385
instances to
memcached
Version
1.3.x
1.3.x
1.3.x
1.3.x