Re: [HACKERS] [PATCH] guc-ify the formerly hard-coded MAX_SEND_SIZE to max_wal_send

On Mon, Jan 9, 2017 at 4:27 PM, Jonathon Nelson wrote: > [I have not done a rigid analysis, here, but...] > > I *think* libpq is the culprit here. > > walsender says "Hey, libpq - please send (up to) 128KB of data!" and doesn't > "return" until it's "sent". Then it sends more. Regardless of the >

Re: [HACKERS] [PATCH] guc-ify the formerly hard-coded MAX_SEND_SIZE to max_wal_send

On Thu, Mar 16, 2017 at 9:59 AM, David Steele wrote: > On 1/9/17 11:33 PM, Jon Nelson wrote: > > > > On Sat, Jan 7, 2017 at 7:48 PM, Jim Nasby > > wrote: > > > > On 1/5/17 12:55 PM, Jonathon Nelson wrote: > > > > Attached please find a patch for Postg

Re: [HACKERS] [PATCH] guc-ify the formerly hard-coded MAX_SEND_SIZE to max_wal_send

On Sat, Jan 7, 2017 at 7:48 PM, Jim Nasby wrote: > On 1/5/17 12:55 PM, Jonathon Nelson wrote: > >> Attached please find a patch for PostgreSQL 9.4 which changes the >> maximum amount of data that the wal sender will send at any point in >> time from the hard-coded value of 128KiB to a user-contro

Re: [HACKERS] [PATCH] guc-ify the formerly hard-coded MAX_SEND_SIZE to max_wal_send

On Sun, Jan 8, 2017 at 11:36 AM, Greg Stark wrote: > On 8 January 2017 at 17:26, Greg Stark wrote: > > On 5 January 2017 at 19:01, Andres Freund wrote: > >> That's a bit odd - shouldn't the OS network stack take care of this in > >> both cases? I mean either is too big for TCP packets (includi

Re: [HACKERS] [PATCH] guc-ify the formerly hard-coded MAX_SEND_SIZE to max_wal_send

On 8 January 2017 at 17:26, Greg Stark wrote: > On 5 January 2017 at 19:01, Andres Freund wrote: >> That's a bit odd - shouldn't the OS network stack take care of this in >> both cases? I mean either is too big for TCP packets (including jumbo >> frames). What type of OS and network is involved

Re: [HACKERS] [PATCH] guc-ify the formerly hard-coded MAX_SEND_SIZE to max_wal_send

On 5 January 2017 at 19:01, Andres Freund wrote: > That's a bit odd - shouldn't the OS network stack take care of this in > both cases? I mean either is too big for TCP packets (including jumbo > frames). What type of OS and network is involved here? 2x may be plausible. The first 128k goes out

Re: [HACKERS] [PATCH] guc-ify the formerly hard-coded MAX_SEND_SIZE to max_wal_send

On 1/5/17 12:55 PM, Jonathon Nelson wrote: Attached please find a patch for PostgreSQL 9.4 which changes the maximum amount of data that the wal sender will send at any point in time from the hard-coded value of 128KiB to a user-controllable value up to 16MiB. It has been primarily tested under 9

Re: [HACKERS] [PATCH] guc-ify the formerly hard-coded MAX_SEND_SIZE to max_wal_send

On Fri, Jan 6, 2017 at 8:52 AM, Kevin Grittner wrote: > On Thu, Jan 5, 2017 at 7:32 PM, Jonathon Nelson wrote: > > On Thu, Jan 5, 2017 at 1:01 PM, Andres Freund > wrote: > >> On 2017-01-05 12:55:44 -0600, Jonathon Nelson wrote: > > >>> In our lab environment and with a 16MiB setting, we saw sub

Re: [HACKERS] [PATCH] guc-ify the formerly hard-coded MAX_SEND_SIZE to max_wal_send

On Thu, Jan 5, 2017 at 7:32 PM, Jonathon Nelson wrote: > On Thu, Jan 5, 2017 at 1:01 PM, Andres Freund wrote: >> On 2017-01-05 12:55:44 -0600, Jonathon Nelson wrote: >>> In our lab environment and with a 16MiB setting, we saw substantially >>> better network utilization (almost 2x!), primarily o

Re: [HACKERS] [PATCH] guc-ify the formerly hard-coded MAX_SEND_SIZE to max_wal_send

On Thu, Jan 5, 2017 at 1:01 PM, Andres Freund wrote: > Hi, > > On 2017-01-05 12:55:44 -0600, Jonathon Nelson wrote: > > Attached please find a patch for PostgreSQL 9.4 which changes the maximum > > amount of data that the wal sender will send at any point in time from > the > > hard-coded value o

Re: [HACKERS] [PATCH] guc-ify the formerly hard-coded MAX_SEND_SIZE to max_wal_send

Hi, On 2017-01-05 12:55:44 -0600, Jonathon Nelson wrote: > Attached please find a patch for PostgreSQL 9.4 which changes the maximum > amount of data that the wal sender will send at any point in time from the > hard-coded value of 128KiB to a user-controllable value up to 16MiB. It has > been pri

[HACKERS] [PATCH] guc-ify the formerly hard-coded MAX_SEND_SIZE to max_wal_send

Attached please find a patch for PostgreSQL 9.4 which changes the maximum amount of data that the wal sender will send at any point in time from the hard-coded value of 128KiB to a user-controllable value up to 16MiB. It has been primarily tested under 9.4 but there has been some testing with 9.5.