Nice, thank you very much.
Are you ok with :
Example :
•Key : test
•Data : 90 bytes
•Flags : 0
Size : (4+1) + (90+2) + (1+2+4) + 48 + 8 = 160 Bytes => Slab 4 (192 Bytes)
Key (characters count) + 1
+ Data (characters count) + 2 bytes ( \r\n )
+ Header
+ Chunk Size
+ CAS Size
Header
key + 1b
val + 2b
item struct 48b
[optional CAS] 8b
then the suffix trailer printf: please read the manpage for snprintf:
snprintf(suffix, 40, " %d %d\r\n", flags, nbytes - 2);
there are four characters in there. two spaces, and then \r and \n. the
two %d's change into: "0" for flags, and "90" fo
The test was :
•Key : test
•Data : 90 bytes
•Flags : 0
:(
Le lundi 16 novembre 2015 19:01:50 UTC+1, Nicolas Martinez a écrit :
>
> Ok... i think i have understood what you say:
>
> Key (Characters Number) + 1 + Data (Characters Number) + Header + Chunk
> Size + CAS Size
>
> Header = Flags (Char
Ok... i think i have understood what you say:
Key (Characters Number) + 1 + Data (Characters Number) + Header + Chunk
Size + CAS Size
Header = Flags (Characters Number) + Key (Characters Numbers)
+ 2 bytes ( \r\n )
+ 4 bytes (2 spaces and 1 \r)
Chunk Size = 48 bytes (default)
CA
Thank you very much for yours answers.
Ok for CAS... i don't use -C so i have to add 8 bytes
i still don"t understand these lines :
>> 2b appended to data_bytes for an extra "\r\n" +
So, \r\n == 2b ?
>> + 4 bytes for spaces and \r\n
which spaces?
What is this \r\n ? Isn't already counted before
Read carefully:
item_size_ok(const size_t nkey, const int flags, const int nbytes) {
passes:
size_t ntotal = item_make_header(nkey + 1, flags, nbytes,
prefix, &nsuffix);
Then conditionally:
if (settings.use_cas) {
ntotal += sizeof(uint64_t);
Hi,
Is CAS always used?
If yes, we have to always add 56 bytes to the KEY and VALUE ?
you don't count FLAGS characters??
I've found that Flags's size (number of characters) impact the storage.
Example:
- Key : 2 characters = 2 bytes
- Value : 28 characters = 28 bytes
- FLAGS : 1 char
The mysql docs don't speak for the main tree... that's their own thing.
the "sizes" binary that comes with the source tree tells you how many
bytes an item will use (though I intend to add this output to the 'stats'
output somewhere). With CAS this is 56 bytes.
56 + 2 + 30 == 88. Class 1 by defau
Add: Memcached version : 1.4.4 (RedHat)
Le samedi 14 novembre 2015 14:49:37 UTC+1, Nicolas Martinez a écrit :
>
> Hi,
> few days i'm reading Memcached documentation and blogs... and i don't
> understand how objects are stored.
>
> *My test*
>
> 3 slabs :
>
>
>- 96.0 Bytes
> - 120.0 By
