On 14/10/13 17:42, Dhiru Kholia wrote: > Hi, > > During the development of "unSPEC" [1] benchmarking suite, I made some > interesting observations regarding prelink. > > - Here are some measurements (for LibreOffice [2] loading time in > seconds) done using the "unSPEC" bench-marking suite. These numbers > are repeatable and you are encouraged to try "unSPEC" to do > independent validation of these numbers. > > - hkario (modern SSD based system, cache flushed): (1.816, 1.811, > 1.797, 1.827 with prelink), (2.034, 2.042, 2.027, 2.016 without > prelink) > > - hkario (modern SSD based system, cache intact): (2.155, 2.121, > 2.101, 2.299 with prelink), (2.311, 2.052, 2.047, 2.037 without > prelink) > > - halfie (T430s): (10.725, 10.095, 10.378, 10.568 with prelink), > (8.901, 8.993, 9.075, 9.448, 9.489 without prelink) > > - danpb (T530): I see basically no measurable difference in times with > or without prelink - quite a lot of variation, but all in same > ballpark, (8.374, 7.849, 8.457, 7.673, 7.608, 8.031, 8.350, 8.183, > 7.381 with prelink), (7.366, 8.009, 7.500, 7.949, 8.208, 8.351, > 7.849, without prelink). > > - For building kernels (using the "kernel-bench" [3] component of unSPEC > suite), prelink saved <= 250 ms over the non-prelink environment > (which took 1m19.138s). hkario even reports worse performance numbers > for the prelink environment. Additionally, we have specialized > softwares like ccache and distcc to solve long-compilation-time > problems. > > In short, we could not distinguish the performance gains of prelink over > the "background noise" in many (or even most) cases. > > So, I was wondering if you are aware of any use-cases where prelink > provides measurable benefits. It would be awesome if you could run > unSPEC on your systems and report back the numbers. > > unSPEC is easy to use and doesn't take much time (or steps) to run. For > more information, please see the following links. > > References: > > [1] https://github.com/kholia/unSPEC > [2] https://github.com/kholia/unSPEC/tree/master/LibreOffice > [3] https://github.com/kholia/unSPEC/tree/master/kernel-bench > > -- > Dhiru > -- > security mailing list > security@xxxxxxxxxxxxxxxxxxxxxxx > https://admin.fedoraproject.org/mailman/listinfo/security > All very well and nice, but what does this have to do with the Security List ? Also, most people will switch off pre-linking on servers, due to erroneous reports of lib and binary changes, that are caused by pre-linking. Regards, Tristan -- Tristan Santore BSc MBCS TS4523-RIPE Network and Infrastructure Operations InterNexusConnect Mobile +44-78-55069812 Tristan.Santore@xxxxxxxxxxxxxxxxxxxxx Former Thawte Notary (Please note: Thawte has closed its WoT programme down, and I am therefore no longer able to accredit trust) For Fedora related issues, please email me at: TSantore@xxxxxxxxxxxxxxxxx -- security mailing list security@xxxxxxxxxxxxxxxxxxxxxxx https://admin.fedoraproject.org/mailman/listinfo/security
