Re: Any sense in this ...?
--0__=88BBE514DF85F92A8f9e8a93df938690918c88BBE514DF85F92A Content-type: multipart/alternative; Boundary="1__=88BBE514DF85F92A8f9e8a93df938690918c88BBE514DF85F92A" --1__=88BBE514DF85F92A8f9e8a93df938690918c88BBE514DF85F92A Content-type: text/plain; charset=US-ASCII Content-transfer-encoding: quoted-printable Yes, it may ..since the whole basis of KAIO is to have an "unblocked" w= ay of doing I/O .. the way we've coded the engine is to make sure whoever = gets to run on the CPU VP will not block it or do any blocked I/O. Since the= KAIO runs on the CPU VP, it might relieve the load on CPU but don't exp= ect a great relief as then you'll have to have AIO VPs to do the I/O and th= ey will do the I/Os using blocked calls. It just might be that your box ne= ed more CPU power/more CPUs in order to handle the load. Thanx much, Rajib Sarkar Advisory Software Engineer DB2/UDB Regional Advanced Support If we all did the things we are capable of doing, we would literally astound ourselves. -- T. Edison = "The Harlequin" = <neil.truby@arden = ta.com> = To Sent by: informix-list@iiug.org = owner-informix-li = cc st@iiug.org = Subj= ect Any sense in this ...? = 01/11/2005 06:54 = PM = = = Please respond to = "The Harlequin" = = = ids v9 what do you think to the theory that turning off kaio might relieve a cpu-bound system? = --1__=88BBE514DF85F92A8f9e8a93df938690918c88BBE514DF85F92A Content-type: text/html; charset=US-ASCII Content-Disposition: inline Content-transfer-encoding: quoted-printable <html><body> <p>Yes, it may ..since the whole basis of KAIO is to have an "unbl= ocked" way of doing I/O .. the way we've coded the engine is to ma= ke sure whoever gets to run on the CPU VP will not block it or do any b= locked I/O. Since the KAIO runs on the CPU VP, it might relieve the loa= d on CPU but don't expect a great relief as then you'll have to have AI= O VPs to do the I/O and they will do the I/Os using blocked calls. It j= ust might be that your box need more CPU power/more CPUs in order to ha= ndle the load. <br> <br> Thanx much,<br> <br> Rajib Sarkar<br> Advisory Software Engineer<br> DB2/UDB Regional Advanced Support<br> <br> <br> If we all did the things we are capable of doing, we would literally as= tound ourselves. -- T. Edison<br> <br> <img src=3D"cid:10__=3D88BBE514DF85F92A8f9e8a93df938@us.ibm.com" width=3D= "16" height=3D"16" alt=3D"Inactive hide details for "The Harlequin= " <neil.truby@ardenta.com>">"The Harlequin" <ne= il.truby@ardenta.com><br> <br> <br> <table width=3D"100%" border=3D"0" cellspacing=3D"0" cellpadding=3D"0">= <tr valign=3D"top"><td style=3D"background-image:url(cid:20__=3D88BBE51= 4DF85F92A8f9e8a93df938@us.ibm.com); background-repeat: no-repeat; " wid= th=3D"40%"> <ul> <ul> <ul> <ul><b><font size=3D"2">"The Harlequin" <neil.truby@ardent= a.com></font></b><font size=3D"2"> </font><br> <font size=3D"2">Sent by: owner-informix-list@iiug.org</font> <p><font size=3D"2">01/11/2005 06:54 PM</font> <table border=3D"1"> <tr valign=3D"top"><td width=3D"168" bgcolor=3D"#FFFFFF"><div align=3D"= center"><font size=3D"2">Please respond to<br> "The Harlequin"</font></div></td></tr> </table> </ul> </ul> </ul> </ul> </td><td width=3D"60%"> <table width=3D"100%" border=3D"0" cellspacing=3D"0" cellpadding=3D"0">= <tr valign=3D"top"><td width=3D"1%" valign=3D"middle"><img src=3D"cid:3= 0__=3D88BBE514DF85F92A8f9e8a93df938@us.ibm.com" border=3D"0" height=3D"= 1" width=3D"58" alt=3D""><br> <div align=3D"right"><font size=3D"2">To</font></div></td><td width=3D"= 100%"><img src=3D"cid:30__=3D88BBE514DF85F92A8f9e8a93df938@us.ibm.com" = border=3D"0" height=3D"1" width=3D"1" alt=3D""><br> <font size=3D"2">informix-list@iiug.org</font></td></tr> <tr valign=3D"top"><td width=3D"1%" valign=3D"middle"><img src=3D"cid:3= 0__=3D88BBE514DF85F92A8f9e8a93df938@us.ibm.com" border=3D"0" height=3D"= 1" width=3D"58" alt=3D""><br> <div align=3D"right"><font size=3D"2">cc</font></div></td><td width=3D"= 100%"><img src=3D"cid:30__=3D88BBE514DF85F92A8f9e8a93df938@us.ibm.com" = border=3D"0" height=3D"1" width=3D"1" alt=3D""><br> </td></tr> <tr valign=3D"top"><td width=3D"1%" valign=3D"middle"><img src=3D"cid:3= 0__=3D88BBE514DF85F92A8f9e8a93df938@us.ibm.com" border=3D"0" height=3D"= 1" width=3D"58" alt=3D""><br> <div align=3D"right"><font size=3D"2">Subject</font></div></td><td widt= h=3D"100%"><img src=3D"cid:30__=3D88BBE514DF85F92A8f9e8a93df938@us.ibm.= com" border=3D"0" height=3D"1" width=3D"1" alt=3D""><br> <font size=3D"2">Any sense in this ...?</font></td></tr> </table> <table border=3D"0" cellspacing=3D"0" cellpadding=3D"0"> <tr valign=3D"top"><td width=3D"58"><img src=3D"cid:30__=3D88BBE514DF85= F92A8f9e8a93df938@us.ibm.com" border=3D"0" height=3D"1" width=3D"1" alt= =3D""></td><td width=3D"336"><img src=3D"cid:30__=3D88BBE514DF85F92A8f9= e8a93df938@us.ibm.com" border=3D"0" height=3D"1" width=3D"1" alt=3D""><= /td></tr> </table> </td></tr> </table> <br> <tt>ids v9<br> what do you think to the theory that turning off kaio
I'm not so sure that I agree with this answer. ;-) If the question were a bottleneck with the CPUVP, then I might. But the question was with a bottleneck on the CPU itself. The AIOVP still has to run on the same CPU and is using the same machine cycles. By using a seperate process which will have to go through all of the std file IO layers, you increase the code path of the IO request as well as increase the code path required by having additional context switches. That said -- if the customer were to switch from KAIO to AIOVPS, and they also reduced the number of AIOVPS so that there was an IO bottleneck, then that might slow down the total processing that could be done in the instance. By throtteling the total work on the system, it might appear that they would get a bit of relief, but of course - that would mean that it would take longer to get the current workload done. This would be a technique of switch a CPU bottleneck for an IO bottleneck. But that's still 'robbing Peter to pay Paul'.... If it is impossible to increase the existing processor power, then you have two other options. 1) be more efficient with what you have (i.e. - tune the system better), or 2) decrease the workload on the system (i.e. - restrict the usage of the system)... M.P. "Rajib Sarkar" <rsarkar@us.ibm.com> wrote in message news:1105510217.d8cdebcc1186959dd68405e0c52aa395@teranews... > > --0__=88BBE514DF85F92A8f9e8a93df938690918c88BBE514DF85F92A > Content-type: multipart/alternative; > Boundary="1__=88BBE514DF85F92A8f9e8a93df938690918c88BBE514DF85F92A" > > --1__=88BBE514DF85F92A8f9e8a93df938690918c88BBE514DF85F92A > Content-type: text/plain; charset=US-ASCII > Content-transfer-encoding: quoted-printable > > > > > > > Yes, it may ..since the whole basis of KAIO is to have an "unblocked" w= > ay > of doing I/O .. the way we've coded the engine is to make sure whoever = > gets > to run on the CPU VP will not block it or do any blocked I/O. Since the= > > KAIO runs on the CPU VP, it might relieve the load on CPU but don't exp= > ect > a great relief as then you'll have to have AIO VPs to do the I/O and th= > ey > will do the I/Os using blocked calls. It just might be that your box ne= > ed > more CPU power/more CPUs in order to handle the load. > > Thanx much, > > Rajib Sarkar > Advisory Software Engineer > DB2/UDB Regional Advanced Support > > > If we all did the things we are capable of doing, we would literally > astound ourselves. -- T. Edison > > > > = > > "The Harlequin" = > > <neil.truby@arden = > > ta.com> = > To > Sent by: informix-list@iiug.org = > > owner-informix-li = > cc > st@iiug.org = > > Subj= > ect > Any sense in this ...? = > > 01/11/2005 06:54 = > > PM = > > = > > = > > Please respond to = > > "The Harlequin" = > > = > > = > > > > > > ids v9 > what do you think to the theory that turning off kaio might relieve a > cpu-bound system? > > > = > > --1__=88BBE514DF85F92A8f9e8a93df938690918c88BBE514DF85F92A > Content-type: text/html; charset=US-ASCII > Content-Disposition: inline > Content-transfer-encoding: quoted-printable > > <html><body> > <p>Yes, it may ..since the whole basis of KAIO is to have an "unbl= > ocked" way of doing I/O .. the way we've coded the engine is to ma= > ke sure whoever gets to run on the CPU VP will not block it or do any b= > locked I/O. Since the KAIO runs on the CPU VP, it might relieve the loa= > d on CPU but don't expect a great relief as then you'll have to have AI= > O VPs to do the I/O and they will do the I/Os using blocked calls. It j= > ust might be that your box need more CPU power/more CPUs in order to ha= > ndle the load. <br> > <br> > Thanx much,<br> > <br> > Rajib Sarkar<br> > Advisory Software Engineer<br> > DB2/UDB Regional Advanced Support<br> > <br> > <br> > If we all did the things we are capable of doing, we would literally as= > tound ourselves. -- T. Edison<br> > <br> > <img src=3D"cid:10__=3D88BBE514DF85F92A8f9e8a93df938@us.ibm.com" width=3D= > "16" height=3D"16" alt=3D"Inactive hide details for "The Harlequin= > " <neil.truby@ardenta.com>">"The Harlequin" <ne= > il.truby@ardenta.com><br> > <br> > <br> > > <table width=3D"100%" border=3D"0" cellspacing=3D"0" cellpadding=3D"0">= > > <tr valign=3D"top"><td style=3D"background-image:url(cid:20__=3D88BBE51= > 4DF85F92A8f9e8a93df938@us.ibm.com); background-repeat: no-repeat; " wid= > th=3D"40%"> > <ul> > <ul> > <ul> > <ul><b><font size=3D"2">"The Harlequin" <neil.truby@ardent= > a.com></font></b><font size=3D"2"> </font><br> > <font size=3D"2">Sent by: owner-informix-list@iiug.org</font> > <p><font size=3D"2">01/11/2005 06:54 PM</font> > <table border=3D"1"> > <tr valign=3D"top"><td width=3D"168" bgcolor=3D"#FFFFFF"><div align=3D"= > center"><font size=3D"2">Please respond to<br> > "The Harlequin"</font></div></td></tr> > </table> > </ul> > </ul> > </ul> > </ul> > </td><td width=3D"60%"> > <table width=3D"100%" border=3D"0" cellspacing=3D"0" cellpadding=3D"0">= > > <tr valign=3D"top"><td width=3D"1%" valign=3D"middle"><img src=3D"cid:3= > 0__=3D88BBE514DF85F92A8f9e8a93df938@us.ibm.com" border=3D"0" height=3D"= > 1" width=3D"58" alt=3D""><br> > <div align=3D"right"><font size=3D"2">To</font></div></td><td width=3D"= > 100%"><img src=3D"cid:30__=3D88BBE514DF85F92A8f9e8a93df938@us.ibm.com" = > border=3D"0" height=3D"1" width=3D"1" alt=3D""><br> > <font size=3D"2">informix-list@iiug.org</font></td></tr> > > <tr valign=3D"top"><td wid