Re: [HACKERS] about fsync in CLOG buffer write

2015-10-06 Thread Robert Haas
On Sun, Oct 4, 2015 at 3:25 PM, Andres Freund wrote: > I don't think it's worth investing time and complexity to bypass SLRU in > certain cases. We should rather rewrite the thing completely. +1. That code is considerably past its sell-by date. -- Robert Haas EnterpriseDB:

Re: [HACKERS] about fsync in CLOG buffer write

2015-10-04 Thread Jeff Janes
On Sat, Sep 12, 2015 at 5:21 PM, Andres Freund wrote: > On September 12, 2015 5:18:28 PM PDT, Jeff Janes > wrote: > >On Wed, Sep 2, 2015 at 5:32 AM, Andres Freund > >wrote: > > > >> On 2015-09-10 19:39:59 +0800, 张广舟(明虚) wrote: > >>

Re: [HACKERS] about fsync in CLOG buffer write

2015-10-04 Thread Andres Freund
On 2015-10-04 12:14:05 -0700, Jeff Janes wrote: > My (naive) expectation is that no additional locking is needed. > > Once we decide to consult the clog, we already know the transaction is no > longer in progress, so it can't be in-flight to change that clog entry we > care about because it was

Re: [HACKERS] about fsync in CLOG buffer write

2015-09-12 Thread Jeff Janes
On Wed, Sep 2, 2015 at 5:32 AM, Andres Freund wrote: > On 2015-09-10 19:39:59 +0800, 张广舟(明虚) wrote: > > We found there is a fsync call when CLOG buffer > > is written out in SlruPhysicalWritePage(). It is often called when a > backend > > needs to check transaction status

Re: [HACKERS] about fsync in CLOG buffer write

2015-09-12 Thread Andres Freund
On September 12, 2015 5:18:28 PM PDT, Jeff Janes wrote: >On Wed, Sep 2, 2015 at 5:32 AM, Andres Freund >wrote: > >> On 2015-09-10 19:39:59 +0800, 张广舟(明虚) wrote: >> > We found there is a fsync call when CLOG buffer >> > is written out in

Re: [HACKERS] about fsync in CLOG buffer write

2015-09-07 Thread 张广舟(明虚)
Andres, Thanks for the reply! I will try the ForwardFsyncRequest-like approach. 在 15-9-2 下午8:32， "Andres Freund" 写入: >On 2015-09-10 19:39:59 +0800, 张广舟(明虚) wrote: >> We found there is a fsync call when CLOG buffer >> is written out in SlruPhysicalWritePage(). It is often

Re: [HACKERS] about fsync in CLOG buffer write

2015-09-02 Thread Andres Freund
On 2015-09-10 19:39:59 +0800, 张广舟(明虚) wrote: > We found there is a fsync call when CLOG buffer > is written out in SlruPhysicalWritePage(). It is often called when a backend > needs to check transaction status with SimpleLruReadPage(). That's when there's not enough buffers available some other,