The problem is not that if I call the controller function if consumes
memory. My problem is that there is something that still reference
something after the execution is finished so the consumed memory never get
released / reused...
2012. május 10., csütörtök 23:27:32 UTC+2 időpontban Martin.Mulone a
következőt írta:
>
> The problem is fetchall(), is getting all the records to memory.
> If you want to iterate a large dataset or not so heavy, but have a table
> with many fields, perhaps you can do it by blocks.
>
> For example using raw sql with dal: example: this fetch by 1000 records
>
> queryraw = "select * from mytable %(limit_query)s"
> def records(query):
> rows = db.executesql(query)
> if rows:
> return True
> else:
> return False
>
> rec = 0
> stage = 0
> block = 1000while True:
> offset = stage * block
> query = queryraw % {'limitquery': 'LIMIT %s, %s' % (offset, block)}
> if not records(query):
> break
>
> rows = db.executesql(query)
> for row in rows:
> rec += 1
> # do something
>
> stage += 1
>
> This is not fast but keep memory low.
>
>
> 2012/5/10 szimszon <[email protected]>
>
>> Could it be related?
>> https://groups.google.com/forum/#!topic/web2py/hmsupVHdDHo/discussion
>> (Memory
>> leak in standalone DAL (issue #731), can you please help test?)
>>
>> 2012. május 10., csütörtök 22:32:53 UTC+2 időpontban szimszon a
>> következőt írta:
>>
>>> Okay. It's clear.
>>>
>>> I'm only puzzled about why the memory didn't get freed or reused after
>>> execution is finished. And if I execute the controller function in 1-2min
>>> interval mem is still not reused.
>>>
>>> So I understand it can eat up the memory but why is all memory locked
>>> forever and didn't get reused - in my understanding (it's not much) in my
>>> case GC do not free mem at all in python level. So some reference is still
>>> intact after function is finished.
>>>
>>>
>>> 2012. május 10., csütörtök 21:53:06 UTC+2 időpontban Richard a
>>> következőt írta:
>>>>
>>>> Ok, you don't need it to works all the time.
>>>>
>>>> Did you get it to update your records?
>>>>
>>>> If not, and if as you said it is a one trip, you can just treat the
>>>> whole records batch by batch...
>>>>
>>>> Look here : http://web2py.com/books/**default/chapter/29/14#**
>>>> Populating-database-with-**dummy-data<http://web2py.com/books/default/chapter/29/14#Populating-database-with-dummy-data>
>>>>
>>>> for i in range(10):
>>>>
>>>>
>>>> populate(db.mytable,100)
>>>>
>>>>
>>>> db.commit()
>>>>
>>>>
>>>> In this example only 100 records are populated at a time between
>>>> db.commit()... So maybe you just have to wrap for loop that will
>>>> db.commit() a couples of time during your processing.
>>>>
>>>> Richard
>>>>
>>>>
>>>> On Thu, May 10, 2012 at 3:32 PM, szimszon <[email protected]> wrote:
>>>>
>>>>> I had to store files and a lot of properties for it. It was in csv.
>>>>> But after I processed it we figured out that not all value was correct in
>>>>> csv but it was a bit redundant. So I can correct it by go through all the
>>>>> records row by row. So that was a one time trip.
>>>>>
>>>>> I just realized after the process I had no memory left. So now I'm
>>>>> investigating what happened...
>>>>>
>>>>> 2012. május 10., csütörtök 21:00:05 UTC+2 időpontban Richard a
>>>>> következőt írta:
>>>>>>
>>>>>> Yes but in this case it is not for the entire reecords...
>>>>>>
>>>>>> Why would you return a full list of all the records?
>>>>>>
>>>>>> I don't understand what is the purpose of listar that you return in
>>>>>> the view under a html table, why do you need to return all the 100000+
>>>>>> entries?
>>>>>>
>>>>>> Richard
>>>>>>
>>>>>> On Thu, May 10, 2012 at 2:56 PM, szimszon <[email protected]> wrote:
>>>>>>
>>>>>>> In book it is a recommended way to iterate over sql results:
>>>>>>>
>>>>>>> http://web2py.com/books/**defaul**t/chapter/29/6<http://web2py.com/books/default/chapter/29/6>
>>>>>>>
>>>>>>> You can do all the steps in one statement:
>>>>>>>
>>>>>>> 1.
>>>>>>> 2.
>>>>>>> 3.
>>>>>>>
>>>>>>> >>> for row in db(db.person.name=='Alex').sel****ect():
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> print row.name
>>>>>>>
>>>>>>>
>>>>>>> Alex
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>> 2012. május 10., csütörtök 20:42:22 UTC+2 időpontban Bruce Wade a
>>>>>>> következőt írta:
>>>>>>>
>>>>>>>> Sorry, you really need to read more about how python works. If you
>>>>>>>> learn how for loops work and memory you will understand the problem.
>>>>>>>>
>>>>>>>> One solution do the query before the for loop then loop through the
>>>>>>>> objects. This may help at bit. Research xrange vs range
>>>>>>>>
>>>>>>>>
>>>>>>>> On Thu, May 10, 2012 at 11:30 AM, szimszon <[email protected]>wrote:
>>>>>>>>
>>>>>>>>> Sorry I don't understand. What do you mean "achieve with join"?
>>>>>>>>>
>>>>>>>>> There is an empty for loop with db.executesql() without join. And
>>>>>>>>> it is eating up the memory. :(
>>>>>>>>>
>>>>>>>>> 2012. május 10., csütörtök 19:12:30 UTC+2 időpontban Richard a
>>>>>>>>> következőt írta:
>>>>>>>>>
>>>>>>>>>> You can't manage what you want to achieve with join?
>>>>>>>>>>
>>>>>>>>>> Richard
>>>>>>>>>>
>>>>>>>>>> On Thu, May 10, 2012 at 10:48 AM, szimszon <[email protected]>wrote:
>>>>>>>>>>
>>>>>>>>>>> Sorry for my dumbness but if something is wrong with my code
>>>>>>>>>>> please point me the right line. I'm not so good in English if it
>>>>>>>>>>> comes to
>>>>>>>>>>> "object instance count" and so. Yeah I know I should go and do some
>>>>>>>>>>> milkmaid job :) but I'm curious.
>>>>>>>>>>>
>>>>>>>>>>> I'm just define some variable:
>>>>>>>>>>>
>>>>>>>>>>> lista = list()
>>>>>>>>>>> last_row = None
>>>>>>>>>>> next_page_number = 0
>>>>>>>>>>>
>>>>>>>>>>> Go in a for loop that just assign the db query result one-by-one
>>>>>>>>>>> to row variable.
>>>>>>>>>>>
>>>>>>>>>>> After that I assign the TABLE() helper to a list variable. That
>>>>>>>>>>> is it.
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> 2012. május 10., csütörtök 16:34:49 UTC+2 időpontban Bruce Wade
>>>>>>>>>>> a következőt írta:
>>>>>>>>>>>
>>>>>>>>>>>> Using direct sql query or DAL is going to cause the exact same
>>>>>>>>>>>> problem in this situation.
>>>>>>>>>>>>
>>>>>>>>>>>> On Thu, May 10, 2012 at 7:28 AM, szimszon
>>>>>>>>>>>> <[email protected]>wrote:
>>>>>>>>>>>>
>>>>>>>>>>>>> It's postgres:// in a
>>>>>>>>>>>>> Version 1.99.7 (2012-04-23 11:26:23) dev of web2py, and
>>>>>>>>>>>>>
>>>>>>>>>>>>> Python 2.7.3 (default, Apr 20 2012, 22:44:07)
>>>>>>>>>>>>> [GCC 4.6.3] on linux2
>>>>>>>>>>>>>
>>>>>>>>>>>>> python-psycopg2 2.4.5-1
>>>>>>>>>>>>>
>>>>>>>>>>>>>
>>>>>>>>>>>>> 2012. május 10., csütörtök 15:40:36 UTC+2 időpontban
>>>>>>>>>>>>> rochacbruno a következőt írta:
>>>>>>>>>>>>>
>>>>>>>>>>>>>> Just for curiosity, what happens if you do it in pure sql?
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> for row in db.executesql("**sele**********ct * from
>>>>>>>>>>>>>> file_properties where id > 0"):
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> # do something
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> Does it have a lower memory usage?
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> On Thu, May 10, 2012 at 4:14 AM, Bruce Wade
>>>>>>>>>>>>>> <<[email protected]>
>>>>>>>>>>>>>> > wrote:
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> for row in db( db.file_**propert**********ies.id > 0 ).
>>>>>>>>>>>>>>> select(
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> --
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> Bruno Rocha
>>>>>>>>>>>>>> [http://rochacbruno.com.br]
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> --
>>>>>>>>>>>> --
>>>>>>>>>>>> Regards,
>>>>>>>>>>>> Bruce Wade
>>>>>>>>>>>> http://ca.linkedin.com/in/**bruc********elwade<http://ca.linkedin.com/in/brucelwade>
>>>>>>>>>>>> http://www.wadecybertech.com
>>>>>>>>>>>> http://www.fittraineronline.**co********m<http://www.fittraineronline.com>-
>>>>>>>>>>>> Fitness Personal Trainers Online
>>>>>>>>>>>> http://www.warplydesigned.com
>>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> --
>>>>>>>> --
>>>>>>>> Regards,
>>>>>>>> Bruce Wade
>>>>>>>> http://ca.linkedin.com/in/**bruc****elwade<http://ca.linkedin.com/in/brucelwade>
>>>>>>>> http://www.wadecybertech.com
>>>>>>>> http://www.fittraineronline.**co****m<http://www.fittraineronline.com>-
>>>>>>>> Fitness Personal Trainers Online
>>>>>>>> http://www.warplydesigned.com
>>>>>>>>
>>>>>>>>
>>>>>>
>>>>
>
>
> --
> http://www.tecnodoc.com.ar
>
>
