Re: [PATCH] lookup_object: prioritize recently found objects

> On Thu, May 02, 2013 at 08:44:07AM +0200, Johannes Sixt wrote:
>> Am 5/1/2013 22:34, schrieb Jeff King:
>>>  struct object *lookup_object(const unsigned char *sha1)
>>>  {
>>> -	unsigned int i;
>>> +	unsigned int i, first;
>>>  	struct object *obj;
>>>  
>>>  	if (!obj_hash)
>>>  		return NULL;
>>>  
>>> -	i = hashtable_index(sha1);
>>> +	first = i = hashtable_index(sha1);
>>>  	while ((obj = obj_hash[i]) != NULL) {
>>>  		if (!hashcmp(sha1, obj->sha1))
>>>  			break;
>>> @@ -85,6 +85,11 @@ struct object *lookup_object(const unsigned char *sha1)
>>>  		if (i == obj_hash_size)
>>>  			i = 0;
>>>  	}
>>> +	if (obj && i != first) {
>>> +		struct object *tmp = obj_hash[i];
>>> +		obj_hash[i] = obj_hash[first];
>>> +		obj_hash[first] = tmp;
>>> +	}
>>>  	return obj;
>>>  }
>>
>> This is one of the places where I think the code does not speak for itself
>> and a comment is warranted: The new if statement is not about correctness,
>> but about optimization:
> 
> I figured the lengthy description in the commit message would be
> sufficient,