Hi, You were right, the method you described worked well. Thanks you!
But so far, could not get any noticeable improvement in Number of transactions / latency. I have tried: 1. At xlog.c, CopyXLogRecordToWAL(int write_len, bool isLogSwitch, XLogRecData *rdata, XLogRecPtr StartPos, XLogRecPtr EndPos), Commenting the memcpy syscall: memcpy(currpos, rdata_data, rdata_len); 2. *XLogInsert(RmgrId rmid, uint8 info), t*he primary insert function in xloginsert.c. I tried commenting the following line at this function, so I can return a phony pointer every time the function is called, just as in bootstrap mode. *if (IsBootstrapProcessingMode() && rmid != RM_XLOG_ID)* 3. At xlog.c, XLogInsertRecord(XLogRecData *rdata, XLogRecPtr fpw_lsn). Commenting the WALInsertLock(s), as well as, commenting the spinlocks around - Update shared LogwrtRqst. (Write, if we crossed page boundary.) 4. The last thing I tried regarding *XLogInsertRecord* function is to comment: "/* * All the record data, including the header, is now ready to be * inserted. Copy the record in the space reserved. */ CopyXLogRecordToWAL(rechdr->xl_tot_len, isLogSwitch, rdata, StartPos, EndPos);" Regards, Netanel On Mon, Jul 11, 2016 at 8:27 AM, Craig Ringer <cr...@2ndquadrant.com> wrote: > On 10 July 2016 at 18:27, Netanel Katzburg <netanel...@gmail.com> wrote: > > >> BUT, both options are not good, as they are stopping me from even running >> i*nitdb.* >> >> >> > The easiest path for testing will be to use an unpatched PostgreSQL to > `initdb` and create a new database. Then start up a patched one that simply > skips WAL writing against an already-`initdb`'d data directory. > > You probably won't be able to safely restart PostgreSQL, but all you're > doing is performance analsys so one-shot operation on a throw-away data > directory is probably fine. > > > -- > Craig Ringer http://www.2ndQuadrant.com/ > PostgreSQL Development, 24x7 Support, Training & Services >
