Hi,David
Seems that the root of evil is in the function(random,trunc),
although I don't know why.
Here is the comparison.
1.w/o function : index is wisely used.(Even without the limit 30 clause)
explain analyze
SELECT md.*
FROM measure_data md
where telegram_id in
(
SELECT 66
常超 wrote
> Hi,all
> I have a table to save received measure data.
>
>
> CREATE TABLE measure_data
> (
> id serial NOT NULL,
> telegram_id integer NOT NULL,
> measure_time timestamp without time zone NOT NULL,
> item_id integer NOT NULL,
> val double precision,
> CONSTRAINT measure_dat
Hi,all
I have a table to save received measure data.
CREATE TABLE measure_data
(
id serial NOT NULL,
telegram_id integer NOT NULL,
measure_time timestamp without time zone NOT NULL,
item_id integer NOT NULL,
val double precision,
CONSTRAINT measure_data_pkey PRIMARY KEY (id)
);
CREAT
Day and night, the postgres stats collector process runs at about 20 MB/sec
output. vmstat shows this:
$ vmstat 2
procs ---memory-- ---swap-- -io -system--
cpu
r b swpd free buff cache si sobibo in cs us sy id
wa
0 0 55864 135740 123804
On Tue, May 13, 2014 at 4:04 PM, Dave Owens wrote:
> Hi,
>
> Apologies for resurrecting this old thread, but it seems like this is
> better than starting a new conversation.
>
> We are now running 9.1.13 and have doubled the CPU and memory. So 2x 16
> Opteron 6276 (32 cores total), and 64GB memo
On Tue, May 13, 2014 at 6:04 PM, Dave Owens wrote:
> Hi,
>
> Apologies for resurrecting this old thread, but it seems like this is
> better than starting a new conversation.
>
> We are now running 9.1.13 and have doubled the CPU and memory. So 2x 16
> Opteron 6276 (32 cores total), and 64GB memo
