Jignesh redid MonetDB’s benchmark
Knowing that MonetDB updated TPC-H benchmark result and indicating that postgresql performance is troublesome, he redid the benchmark on his own.
I redid a quick test with the same workload on one of my systems with SF
10 which is about 10GB
(I hope it comes out properly displayed)Jignesh From Monet (8.3T/8.2.9)
..details skipped. Follow the link to see …
All time is in seconds (sub seconds where availabe)
Ratio > 1 means 8.3.3 is slower and <1 means 8.3.3 is fasterMy take on the results:
* I had to tweak the statement of Q1 in order to execute it.
(TPC-H kit does not directly support POSTGRESQL statements)* Timings with 8.3.3 and bit of tuning gives much better time overall
This was expected (Some queries finish in 7% of the time than what
MonetDB reported. From the queries that worked only Q7 & Q21 seem to
have regressed)* However Empty rows results is occuring consistently
(Infact Q11 also returned empty for me while it worked in their test)
Queries: 4,5,6,10,11,12,14,15
(ACTION ITEM: I will start separate threads for each of those queries in
HACKERS alias to figure out the problem since it looks like Functional
problem to me and should be interesting to hackers alias)* Two queries 17,20 looks like will not finish (I let Q17 to run for 18 hrs and yet it had not completed. As for Q20 I killed it as it was approaching
an hour.)
(ACTION ITEM: Not sure whether debugging for these queries will go in
hackers or perform alias but I will start a thread on them too.)* Looks like bit of tuning is required for Q1, Q7, Q9, Q21 to improve their
overall time. Specially understanding if PostgreSQL is missing a more
efficient plan for them.
(ACTION ITEM: I will start separate threads on performance alias to
dig into those queries)I hope to start separate threads for each queries so we can track them
easier. I hope to provide explain analyze outputs for each one of them
and lets see if there are any problems.Feedback welcome on what you want to see for each threads.
Regards,
Jignesh
Many factors affecting postges performance
found here. Maybe I’ll revisit this.
But there are so many variables involved in
database tuning as to make such a claim hard to swallow. For instance
. . .
> fits their system best? I figure (somewhat simplistically) that most
> settings are more related to available memory than anything else, so
. . . your figuring here is indeed simplistic. Every day I see
requests for help from people who have followed the rule of thumb “1/4
of memory for shared_buffers”, except that they’re also running
apache+jakarta, MySQL, and a mail server on the same box. They wonder
why the stock advice is so wrong. It’s wrong because a
general-purpose tool is almost never going to come pre-set for every
possible workload you might want to throw at it. So even “how much
memory” there is on the machine is a question that is harder to answer
than it might seem. Disk layout, data access patterns, even the
filesystem you choose can make significant differences in how the
system performs.
riven walkthrough
Just a quickie.
I found that, AFAIK, thescarletspider2 made the best Riven Walkthrough.
Prince of Persia Sands of Time Playthrough
Wandering, I found two optimal PoP TSoT playthrough recordings.
The first, also available in HQ format, is named Let’s Play Prince of Persia The Sands of Time. They include the voice of the player, and the sound is not clear. I think they’re vidcam recordings.
The second, is here. It has clearer sound, but is not available in HQ video format.
Sounds of hard drive crashing
I found here lots of MP3 files of HDD crashing sound. Cool. Maybe useful also. 
Layar OLED lipat dari Samsung
Aku dapat dari reghardware sebuah video menarik dari Samsung yang mendemokan layar display lebar yang dapat dilipat menjadi ponsel.
Rasanya penjelasanku masih kurang jelas. Lihat saja langsung di bawah ini.
Forbes listed ten Apple failures / flops
OSNews published a link to Forbes article that listed Apple’s failure.
An interresting point there is that OSNews disagrees on Forbes’ point at Lisa as a flop.
Some of the concepts of the Macintosh were pioneered by the Lisa team, such as Quickdraw, one of the fundamental components of the Mac OS. In addition, as the stories on Folklore.org point out, the competition between the Mac and Lisa teams propelled both teams to excel at what they were doing. From this perspective, the Lisa wasn’t a failure at all.
It’s either Forbes doesn’t know this fact, or it means nothing for it. If Lisa doesn’t sale, it’s a flop. Typical of business people’s point of view.
PS interface on desktop
Wouldn’t you like it if you could have crossbar interface like seen at PS3 and PSP for your desktop? SkyOS has it.
Nasib majalah “Aku Tahu”
Hari ini aku lihat-lihat dashboard wordpress ku, di antara yang sampai ke blog ini ada yang lewat pencarian majalah “Aku Tahu”.
Majalah itu salah satu majalah favoritku di masa kecilku. Majalah itu adalah majalah tentang sains. Salah satu artikel yang paling kuingat adalah ulasannya tentang Pedang Damaskus yang luar biasa lentur dan tajam, serta metode pembuatannya yang tidak biasa menurut teknologi saat itu. Banyak juga artikel yang disumbangkan oleh pembaca. Ada juga yang beritahukan bahwa 355/113 itu lebih mendekati bilangan PI daripada 22/7, lebih mudah dihapal, lagi (tinggal tulis 113355 dan pilah dua di tengah).
Sekarang majalah itu sudah mendiang. Dicari di gugel pun tlah tiada bekas. Sedih banget karena itu tunjukkan betapa ilmu gak dihargai.
2*2 is ?
Several scientists were all posed the following question: “What is 2 * 2 ?”
The engineer whips out his slide rule (so it’s old) and shuffles it back and forth, and finally announces “3.99″.
The physicist consults his technical references, sets up the problem on his computer, and announces “it lies between 3.98 and 4.02″.
The mathematician cogitates for a while, then announces: “I don’t know what the answer is, but I can tell you, an answer exists!”.
Philosopher smiles: “But what do you mean by 2 * 2 ?”
Logician replies: “Please define 2 * 2 more precisely.”
The sociologist: “I don’t know, but is was nice talking about it”.
Behavioral Ecologist: “A polygamous mating system”.
Medical Student : “4″ All others looking astonished : “How did you know ??” Medical Student : :I memorized it.”
