[SR-Users] Hash Table capacity

[Olle E. Johansson]

19 aug 2013 kl. 17:02 skrev Elena-Ramona Modroiu <ramona at asipto.com>:

> Hi,
> 
> On 8/19/13 4:05 PM, Alex Balashov wrote:
>> According the docs, the hash table is restricted to a maximum size of 2^16 (65536) buckets. 
> it was restricted to 2^14, I just lifted it to positive integer range 2^31 because it is easier to get now systems with plenty of memory -- it will be in next major release.
> 
>> 
>> This doesn't mean that the htable can only hold 65k entries, just that it's the maximum number of unique buckets. Assuming a theoretically ideal distribution where every value has a unique bucket, after 65k values, you will get collisions. Collision chains attached to buckets are linear lists. After collision chains get deep, performance becomes more and more linear. 
>> 
>> So, you can put 2m values into the htable. I am not sure that it is the optimal use of an htable, however. 
> 
> With the previous upper limit (2^14) you could get a fair distribution of about 125 items per slot, which is still fine for linear searching, provided a modern CPU server.
> 
> You can simulate some tests and measure the search performances with benchmark module.
When you do, please share the results! 
- How long time does it take to load/reload such a big hash table?

/O
> 
> Regards,
> Ramona
> 
>> 
>> 
>> Ricardo Martinez <rmartinez at redvoiss.net> wrote:
>> Anyone here?
>> Thanks!
>>  
>> Ricardo.-
>>  
>> De: Ricardo Martinez [mailto:rmartinez at redvoiss.net] 
>> Enviado el: miércoles, 14 de agosto de 2013 18:34
>> Para: sr-users at lists.sip-router.org
>> Asunto: Hash Table capacity
>>  
>> Hello list.
>> I have a question about the HTABLE module.  Suppose that I have a mysql database with 2 million of records.  Is possible to load this table as a hash table compatible with Kamailio!?
>>  
>> Hope someone can help me.
>>  
>> Thanks,
>> Ricardo Martinez.-
>>  
>> 
>> SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing list
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>> --
>> Sent from my mobile, and thus lacking in the refinement one might expect from a fully fledged keyboard. 
>> 
>> Alex Balashov - Principal
>> Evariste Systems LLC
>> 235 E Ponce de Leon Ave
>> Suite 106
>> Decatur, GA 30030
>> United States
>> Tel: +1-678-954-0670
>> Web: http://www.evaristesys.com/, http://www.alexbalashov.com 
>> 
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