Re: [google-appengine] Re: GAE for CPU intensive time important application
On Sat, Nov 28, 2009 at 5:13 PM, Eric wrote: > Another question, you both recommended Python for some of its > features, but isn't Python much slower than Java? So wouldn't that > necessitate many more instances/CPUs to keep with the query load? Yes, the python VM is slower than JVM. Python dev and prototyping time however amazingly faster and less frustrating. I recommend anybody avoid xml and use beautiful yaml whenever able. Both py and java can use just function or static method which won't create instance, very fast and no proof here you can't do everything in Java with static methods or likewise python withno classas, just functions. Example advance python phonetic algorithm, just a function, no class http://atomboy.isa-geek.com/plone/Members/acoil/programing/double-metaphone/metaphone.py/at_download/file or a snippet I posted in python than will be a mess in java, 23 rows in python refactorable to half http://www.djangosnippets.org/snippets/1821/ good luck Niklas (montao.googlecode.com) -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To post to this group, send email to google-appeng...@googlegroups.com. To unsubscribe from this group, send email to google-appengine+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en.
Re: [google-appengine] Re: GAE for CPU intensive time important application
2009/11/29 Eric : > Thanks for all your comments. > Regarding Python/Java speed, 99% of the runtime is spent iterating in > an attempt to converge to some numerical solution . > Loops, arithmetic and memory updates. I would guess an interpreted > language like Python (am I right?) would be much slower. > You can try a simulation test before your decision. > About the instance set up time, I agree that if query frequency > suddenly rises from 100/sec to 200/sec the system I suggested would > stall, but I'm don't think I'm expecting such drastic changes in a > small amount of time. > Regarding my suggestion on new instance creation, don't I have a say > on when and how that happens? Or is it totally up to AppEngine to > define when a new instance is created? Can I, for example, have 10 > instances that are simply waiting for situations like Keakon > described? At least not right now, It's up to the app master. http://code.google.com/events/io/2009/sessions/FromSparkPlugToDriveTrain.html > I'm trying to form some intuitive picture of how GAE works by guessing > and hoping to be corrected by someone when/if I'm wrong. > Maybe I require a cloud platform that allows tinkering at lower > levels? > > On Nov 28, 9:54 pm, Andy Freeman wrote: >> > Maybe I don't understand something, but why should the 5 second setup >> > on a new instance bother me? A new instance should be created when >> > other instances are near capacity, and not when they exceed it, right? >> > So once initialized it can be "dummy-run" internally and only >> > available 5 seconds later while the existing instance continue to take >> > care of the incoming queries. >> >> What makes you think that the request that causes the creation of a >> new instance doesn't wait for the creation of said instance? (The >> scheme you suggest is plausible, but why do you think that it's how >> appengine works?) >> >> On Nov 28, 9:03 am, Eric wrote: >> >> > Thanks for the response. >> >> > Maybe I don't understand something, but why should the 5 second setup >> > on a new instance bother me? A new instance should be created when >> > other instances are near capacity, and not when they exceed it, right? >> > So once initialized it can be "dummy-run" internally and only >> > available 5 seconds later while the existing instance continue to take >> > care of the incoming queries. >> >> > Also, do you think the latency requirements are realistic with GAE? >> > That is, in the ordinary case, could the response be consistently >> > served back to the querying user with delay of max 3 seconds? >> >> > On Nov 28, 8:35 am, 风笑雪 wrote: >> >> > > The White House hosted an online town hall meeting on GAE with GWT, >> > > and received 700 hits per second at its >> > > peak.http://google-code-updates.blogspot.com/2009/04/google-developer-prod... >> >> > > But more than 1000 queries a second is never been tested. >> >> > > I think Java is not a good choice in your case. When your user >> > > suddenly increasing, starting a new Jave instance may cost more than 5 >> > > seconds, while Python needs less than 1 second. >> >> > > 2009/11/27 Eric : >> >> > > > Hi, >> >> > > > I wish to set up a CPU-intensive time-important query service for >> > > > users on the internet. >> > > > Is GAE with Java the right choice? (as compared to other clouds, or >> > > > non-cloud architecture) >> > > > Specifically, in terms of: >> > > > 1) pricing >> > > > 2) latency resulting from slow CPU, JIT compiles, etc.. >> > > > 3) latency resulting from communication of processes inside the cloud >> > > > (e.g. a queuing process and a calculation process) >> > > > 4) latency of communication between cloud and end user >> >> > > > A usage scenario I am expecting is: >> > > > - a typical user sends a query (XML of size around 1K) once every 30 >> > > > seconds on average, >> > > > - Each query requires a numerical computation of average time 0.2 sec >> > > > and max time 1 sec (on a 1 GHz Pentium). The computation requires no >> > > > data other than the query itself. >> > > > - The delay a user experiences between sending a query and receiving a >> > > > response should be on average no more than 2 seconds and in general no >> > > > more than 5 seconds. >> > > > - A background save to a DB of the response should occur (not time >> > > > critical) >> > > > - There can be up to 3 simultaneous users - i.e., on average 1000 >> > > > queries a second, each requiring an average 0.2 sec calculation, so >> > > > that would necessitate around 200 CPUs. >> >> > > > Is this feasible on GAE Java? >> > > > If so, where can I learn about the correct design methodology for such >> > > > a project on GAE? >> >> > > > If this is the wrong forum to ask this, I'd appreciate redirection. >> >> > > > Thanks, >> >> > > > Eric >> >> > > > -- >> >> > > > You received this message because you are subscribed to the Google >> > > > Groups "Google App Engine" group. >> > > > To post to this group, send email to google
[google-appengine] Re: GAE for CPU intensive time important application
Thanks for all your comments. Regarding Python/Java speed, 99% of the runtime is spent iterating in an attempt to converge to some numerical solution . Loops, arithmetic and memory updates. I would guess an interpreted language like Python (am I right?) would be much slower. About the instance set up time, I agree that if query frequency suddenly rises from 100/sec to 200/sec the system I suggested would stall, but I'm don't think I'm expecting such drastic changes in a small amount of time. Regarding my suggestion on new instance creation, don't I have a say on when and how that happens? Or is it totally up to AppEngine to define when a new instance is created? Can I, for example, have 10 instances that are simply waiting for situations like Keakon described? I'm trying to form some intuitive picture of how GAE works by guessing and hoping to be corrected by someone when/if I'm wrong. Maybe I require a cloud platform that allows tinkering at lower levels? On Nov 28, 9:54 pm, Andy Freeman wrote: > > Maybe I don't understand something, but why should the 5 second setup > > on a new instance bother me? A new instance should be created when > > other instances are near capacity, and not when they exceed it, right? > > So once initialized it can be "dummy-run" internally and only > > available 5 seconds later while the existing instance continue to take > > care of the incoming queries. > > What makes you think that the request that causes the creation of a > new instance doesn't wait for the creation of said instance? (The > scheme you suggest is plausible, but why do you think that it's how > appengine works?) > > On Nov 28, 9:03 am, Eric wrote: > > > Thanks for the response. > > > Maybe I don't understand something, but why should the 5 second setup > > on a new instance bother me? A new instance should be created when > > other instances are near capacity, and not when they exceed it, right? > > So once initialized it can be "dummy-run" internally and only > > available 5 seconds later while the existing instance continue to take > > care of the incoming queries. > > > Also, do you think the latency requirements are realistic with GAE? > > That is, in the ordinary case, could the response be consistently > > served back to the querying user with delay of max 3 seconds? > > > On Nov 28, 8:35 am, 风笑雪 wrote: > > > > The White House hosted an online town hall meeting on GAE with GWT, > > > and received 700 hits per second at its > > > peak.http://google-code-updates.blogspot.com/2009/04/google-developer-prod... > > > > But more than 1000 queries a second is never been tested. > > > > I think Java is not a good choice in your case. When your user > > > suddenly increasing, starting a new Jave instance may cost more than 5 > > > seconds, while Python needs less than 1 second. > > > > 2009/11/27 Eric : > > > > > Hi, > > > > > I wish to set up a CPU-intensive time-important query service for > > > > users on the internet. > > > > Is GAE with Java the right choice? (as compared to other clouds, or > > > > non-cloud architecture) > > > > Specifically, in terms of: > > > > 1) pricing > > > > 2) latency resulting from slow CPU, JIT compiles, etc.. > > > > 3) latency resulting from communication of processes inside the cloud > > > > (e.g. a queuing process and a calculation process) > > > > 4) latency of communication between cloud and end user > > > > > A usage scenario I am expecting is: > > > > - a typical user sends a query (XML of size around 1K) once every 30 > > > > seconds on average, > > > > - Each query requires a numerical computation of average time 0.2 sec > > > > and max time 1 sec (on a 1 GHz Pentium). The computation requires no > > > > data other than the query itself. > > > > - The delay a user experiences between sending a query and receiving a > > > > response should be on average no more than 2 seconds and in general no > > > > more than 5 seconds. > > > > - A background save to a DB of the response should occur (not time > > > > critical) > > > > - There can be up to 3 simultaneous users - i.e., on average 1000 > > > > queries a second, each requiring an average 0.2 sec calculation, so > > > > that would necessitate around 200 CPUs. > > > > > Is this feasible on GAE Java? > > > > If so, where can I learn about the correct design methodology for such > > > > a project on GAE? > > > > > If this is the wrong forum to ask this, I'd appreciate redirection. > > > > > Thanks, > > > > > Eric > > > > > -- > > > > > You received this message because you are subscribed to the Google > > > > Groups "Google App Engine" group. > > > > To post to this group, send email to google-appeng...@googlegroups.com. > > > > To unsubscribe from this group, send email to > > > > google-appengine+unsubscr...@googlegroups.com. > > > > For more options, visit this group > > > > athttp://groups.google.com/group/google-appengine?hl=en.-Hide quoted > > > > text - > > > - Show quoted text - -- You received this m
[google-appengine] Re: GAE for CPU intensive time important application
> Maybe I don't understand something, but why should the 5 second setup > on a new instance bother me? A new instance should be created when > other instances are near capacity, and not when they exceed it, right? > So once initialized it can be "dummy-run" internally and only > available 5 seconds later while the existing instance continue to take > care of the incoming queries. What makes you think that the request that causes the creation of a new instance doesn't wait for the creation of said instance? (The scheme you suggest is plausible, but why do you think that it's how appengine works?) On Nov 28, 9:03 am, Eric wrote: > Thanks for the response. > > Maybe I don't understand something, but why should the 5 second setup > on a new instance bother me? A new instance should be created when > other instances are near capacity, and not when they exceed it, right? > So once initialized it can be "dummy-run" internally and only > available 5 seconds later while the existing instance continue to take > care of the incoming queries. > > Also, do you think the latency requirements are realistic with GAE? > That is, in the ordinary case, could the response be consistently > served back to the querying user with delay of max 3 seconds? > > On Nov 28, 8:35 am, 风笑雪 wrote: > > > > > The White House hosted an online town hall meeting on GAE with GWT, > > and received 700 hits per second at its > > peak.http://google-code-updates.blogspot.com/2009/04/google-developer-prod... > > > But more than 1000 queries a second is never been tested. > > > I think Java is not a good choice in your case. When your user > > suddenly increasing, starting a new Jave instance may cost more than 5 > > seconds, while Python needs less than 1 second. > > > 2009/11/27 Eric : > > > > Hi, > > > > I wish to set up a CPU-intensive time-important query service for > > > users on the internet. > > > Is GAE with Java the right choice? (as compared to other clouds, or > > > non-cloud architecture) > > > Specifically, in terms of: > > > 1) pricing > > > 2) latency resulting from slow CPU, JIT compiles, etc.. > > > 3) latency resulting from communication of processes inside the cloud > > > (e.g. a queuing process and a calculation process) > > > 4) latency of communication between cloud and end user > > > > A usage scenario I am expecting is: > > > - a typical user sends a query (XML of size around 1K) once every 30 > > > seconds on average, > > > - Each query requires a numerical computation of average time 0.2 sec > > > and max time 1 sec (on a 1 GHz Pentium). The computation requires no > > > data other than the query itself. > > > - The delay a user experiences between sending a query and receiving a > > > response should be on average no more than 2 seconds and in general no > > > more than 5 seconds. > > > - A background save to a DB of the response should occur (not time > > > critical) > > > - There can be up to 3 simultaneous users - i.e., on average 1000 > > > queries a second, each requiring an average 0.2 sec calculation, so > > > that would necessitate around 200 CPUs. > > > > Is this feasible on GAE Java? > > > If so, where can I learn about the correct design methodology for such > > > a project on GAE? > > > > If this is the wrong forum to ask this, I'd appreciate redirection. > > > > Thanks, > > > > Eric > > > > -- > > > > You received this message because you are subscribed to the Google Groups > > > "Google App Engine" group. > > > To post to this group, send email to google-appeng...@googlegroups.com. > > > To unsubscribe from this group, send email to > > > google-appengine+unsubscr...@googlegroups.com. > > > For more options, visit this group > > > athttp://groups.google.com/group/google-appengine?hl=en.- Hide quoted > > > text - > > - Show quoted text - -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To post to this group, send email to google-appeng...@googlegroups.com. To unsubscribe from this group, send email to google-appengine+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en.
[google-appengine] Re: GAE for CPU intensive time important application
> Another question, you both recommended Python for some of its > features, but isn't Python much slower than Java? Maybe, maybe not, but it may not matter. What fraction of your run- time actually depends on language speed? On Nov 28, 9:13 am, Eric wrote: > Another question, you both recommended Python for some of its > features, but isn't Python much slower than Java? So wouldn't that > necessitate many more instances/CPUs to keep with the query load? > > On Nov 28, 9:45 am, Niklas Rosencrantz wrote: > > > > > >> 1) pricing > > > absolutely seems so. gae apps 1/20 cheaper than previous > > hostingmethods (servers)>> 2) latency resulting from slow CPU, JIT > > compiles, etc. > > > latency oriented group we don't focus > > onhttp://groups.google.com/group/make-the-web-faster > > in the long run, yes. you can compare to dedicated physical server, > > much more difficult to configure, compile modules spec for physical > > architecture, get superiour response time with C++ server pages ouput > > "hello world" while best project is security and convenience are > > kings. latency least prio still important. > > > python is good, same thing in python 1/10 code compared to java, no > > XML, yaml very neat. java strong point: more ways to solve same > > problem. > > > On Sat, Nov 28, 2009 at 6:35 AM, 风笑雪 wrote: > > > The White House hosted an online town hall meeting on GAE with GWT, > > > and received 700 hits per second at its peak. > > >http://google-code-updates.blogspot.com/2009/04/google-developer-prod... > > > > But more than 1000 queries a second is never been tested. > > > > I think Java is not a good choice in your case. When your user > > > suddenly increasing, starting a new Jave instance may cost more than 5 > > > seconds, while Python needs less than 1 second. > > > > 2009/11/27 Eric : > > > >> Hi, > > > >> I wish to set up a CPU-intensive time-important query service for > > >> users on the internet. > > >> Is GAE with Java the right choice? (as compared to other clouds, or > > >> non-cloud architecture) > > >> Specifically, in terms of: > > >> 1) pricing > > >> 2) latency resulting from slow CPU, JIT compiles, etc.. > > >> 3) latency resulting from communication of processes inside the cloud > > >> (e.g. a queuing process and a calculation process) > > >> 4) latency of communication between cloud and end user > > > >> A usage scenario I am expecting is: > > >> - a typical user sends a query (XML of size around 1K) once every 30 > > >> seconds on average, > > >> - Each query requires a numerical computation of average time 0.2 sec > > >> and max time 1 sec (on a 1 GHz Pentium). The computation requires no > > >> data other than the query itself. > > >> - The delay a user experiences between sending a query and receiving a > > >> response should be on average no more than 2 seconds and in general no > > >> more than 5 seconds. > > >> - A background save to a DB of the response should occur (not time > > >> critical) > > >> - There can be up to 3 simultaneous users - i.e., on average 1000 > > >> queries a second, each requiring an average 0.2 sec calculation, so > > >> that would necessitate around 200 CPUs. > > > >> Is this feasible on GAE Java? > > >> If so, where can I learn about the correct design methodology for such > > >> a project on GAE? > > > >> If this is the wrong forum to ask this, I'd appreciate redirection. > > > >> Thanks, > > > >> Eric > > > >> -- > > > >> You received this message because you are subscribed to the Google > > >> Groups "Google App Engine" group. > > >> To post to this group, send email to google-appeng...@googlegroups.com. > > >> To unsubscribe from this group, send email to > > >> google-appengine+unsubscr...@googlegroups.com. > > >> For more options, visit this group > > >> athttp://groups.google.com/group/google-appengine?hl=en. > > > > -- > > > > You received this message because you are subscribed to the Google Groups > > > "Google App Engine" group. > > > To post to this group, send email to google-appeng...@googlegroups.com. > > > To unsubscribe from this group, send email to > > > google-appengine+unsubscr...@googlegroups.com. > > > For more options, visit this group > > > athttp://groups.google.com/group/google-appengine?hl=en.- Hide quoted > > > text - > > - Show quoted text - -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To post to this group, send email to google-appeng...@googlegroups.com. To unsubscribe from this group, send email to google-appengine+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en.
Re: [google-appengine] Re: GAE for CPU intensive time important application
An app instance cannot serve 2 request at the same time. Suppose you have 100 requests/sec, and GAE offers 100 app instances to serve these requests. At one time it suddenly raise up to 200 requests/sec, so GAE tries to create 100 more app instances to serve. But create a new Java instance may need more than 5 seconds, in these 5 seconds, 500 requests have to wait, and new requests are still coming. So GAE create even more app instances, maybe 50, 100 or 200, and kill them when the 500 requests have been finished. Thus I think Java will waste much more time than Python. Query between Python and Java is almost the same speed, but you need low-level api for batch query: http://gaejava.appspot.com/ 2009/11/29 Eric : > Another question, you both recommended Python for some of its > features, but isn't Python much slower than Java? So wouldn't that > necessitate many more instances/CPUs to keep with the query load? > > On Nov 28, 9:45 am, Niklas Rosencrantz wrote: >> >> 1) pricing >> >> absolutely seems so. gae apps 1/20 cheaper than previous >> hostingmethods (servers)>> 2) latency resulting from slow CPU, JIT compiles, >> etc. >> >> latency oriented group we don't focus >> onhttp://groups.google.com/group/make-the-web-faster >> in the long run, yes. you can compare to dedicated physical server, >> much more difficult to configure, compile modules spec for physical >> architecture, get superiour response time with C++ server pages ouput >> "hello world" while best project is security and convenience are >> kings. latency least prio still important. >> >> python is good, same thing in python 1/10 code compared to java, no >> XML, yaml very neat. java strong point: more ways to solve same >> problem. >> >> On Sat, Nov 28, 2009 at 6:35 AM, 风笑雪 wrote: >> > The White House hosted an online town hall meeting on GAE with GWT, >> > and received 700 hits per second at its peak. >> >http://google-code-updates.blogspot.com/2009/04/google-developer-prod... >> >> > But more than 1000 queries a second is never been tested. >> >> > I think Java is not a good choice in your case. When your user >> > suddenly increasing, starting a new Jave instance may cost more than 5 >> > seconds, while Python needs less than 1 second. >> >> > 2009/11/27 Eric : >> >> >> Hi, >> >> >> I wish to set up a CPU-intensive time-important query service for >> >> users on the internet. >> >> Is GAE with Java the right choice? (as compared to other clouds, or >> >> non-cloud architecture) >> >> Specifically, in terms of: >> >> 1) pricing >> >> 2) latency resulting from slow CPU, JIT compiles, etc.. >> >> 3) latency resulting from communication of processes inside the cloud >> >> (e.g. a queuing process and a calculation process) >> >> 4) latency of communication between cloud and end user >> >> >> A usage scenario I am expecting is: >> >> - a typical user sends a query (XML of size around 1K) once every 30 >> >> seconds on average, >> >> - Each query requires a numerical computation of average time 0.2 sec >> >> and max time 1 sec (on a 1 GHz Pentium). The computation requires no >> >> data other than the query itself. >> >> - The delay a user experiences between sending a query and receiving a >> >> response should be on average no more than 2 seconds and in general no >> >> more than 5 seconds. >> >> - A background save to a DB of the response should occur (not time >> >> critical) >> >> - There can be up to 3 simultaneous users - i.e., on average 1000 >> >> queries a second, each requiring an average 0.2 sec calculation, so >> >> that would necessitate around 200 CPUs. >> >> >> Is this feasible on GAE Java? >> >> If so, where can I learn about the correct design methodology for such >> >> a project on GAE? >> >> >> If this is the wrong forum to ask this, I'd appreciate redirection. >> >> >> Thanks, >> >> >> Eric >> >> >> -- >> >> >> You received this message because you are subscribed to the Google Groups >> >> "Google App Engine" group. >> >> To post to this group, send email to google-appeng...@googlegroups.com. >> >> To unsubscribe from this group, send email to >> >> google-appengine+unsubscr...@googlegroups.com. >> >> For more options, visit this group >> >> athttp://groups.google.com/group/google-appengine?hl=en. >> >> > -- >> >> > You received this message because you are subscribed to the Google Groups >> > "Google App Engine" group. >> > To post to this group, send email to google-appeng...@googlegroups.com. >> > To unsubscribe from this group, send email to >> > google-appengine+unsubscr...@googlegroups.com. >> > For more options, visit this group >> > athttp://groups.google.com/group/google-appengine?hl=en. > > -- > > You received this message because you are subscribed to the Google Groups > "Google App Engine" group. > To post to this group, send email to google-appeng...@googlegroups.com. > To unsubscribe from this group, send email to > google-appengine+unsubscr...@googlegroups.com. > For more options, visit this gr
[google-appengine] Re: GAE for CPU intensive time important application
Another question, you both recommended Python for some of its features, but isn't Python much slower than Java? So wouldn't that necessitate many more instances/CPUs to keep with the query load? On Nov 28, 9:45 am, Niklas Rosencrantz wrote: > >> 1) pricing > > absolutely seems so. gae apps 1/20 cheaper than previous > hostingmethods (servers)>> 2) latency resulting from slow CPU, JIT compiles, > etc. > > latency oriented group we don't focus > onhttp://groups.google.com/group/make-the-web-faster > in the long run, yes. you can compare to dedicated physical server, > much more difficult to configure, compile modules spec for physical > architecture, get superiour response time with C++ server pages ouput > "hello world" while best project is security and convenience are > kings. latency least prio still important. > > python is good, same thing in python 1/10 code compared to java, no > XML, yaml very neat. java strong point: more ways to solve same > problem. > > On Sat, Nov 28, 2009 at 6:35 AM, 风笑雪 wrote: > > The White House hosted an online town hall meeting on GAE with GWT, > > and received 700 hits per second at its peak. > >http://google-code-updates.blogspot.com/2009/04/google-developer-prod... > > > But more than 1000 queries a second is never been tested. > > > I think Java is not a good choice in your case. When your user > > suddenly increasing, starting a new Jave instance may cost more than 5 > > seconds, while Python needs less than 1 second. > > > 2009/11/27 Eric : > > >> Hi, > > >> I wish to set up a CPU-intensive time-important query service for > >> users on the internet. > >> Is GAE with Java the right choice? (as compared to other clouds, or > >> non-cloud architecture) > >> Specifically, in terms of: > >> 1) pricing > >> 2) latency resulting from slow CPU, JIT compiles, etc.. > >> 3) latency resulting from communication of processes inside the cloud > >> (e.g. a queuing process and a calculation process) > >> 4) latency of communication between cloud and end user > > >> A usage scenario I am expecting is: > >> - a typical user sends a query (XML of size around 1K) once every 30 > >> seconds on average, > >> - Each query requires a numerical computation of average time 0.2 sec > >> and max time 1 sec (on a 1 GHz Pentium). The computation requires no > >> data other than the query itself. > >> - The delay a user experiences between sending a query and receiving a > >> response should be on average no more than 2 seconds and in general no > >> more than 5 seconds. > >> - A background save to a DB of the response should occur (not time > >> critical) > >> - There can be up to 3 simultaneous users - i.e., on average 1000 > >> queries a second, each requiring an average 0.2 sec calculation, so > >> that would necessitate around 200 CPUs. > > >> Is this feasible on GAE Java? > >> If so, where can I learn about the correct design methodology for such > >> a project on GAE? > > >> If this is the wrong forum to ask this, I'd appreciate redirection. > > >> Thanks, > > >> Eric > > >> -- > > >> You received this message because you are subscribed to the Google Groups > >> "Google App Engine" group. > >> To post to this group, send email to google-appeng...@googlegroups.com. > >> To unsubscribe from this group, send email to > >> google-appengine+unsubscr...@googlegroups.com. > >> For more options, visit this group > >> athttp://groups.google.com/group/google-appengine?hl=en. > > > -- > > > You received this message because you are subscribed to the Google Groups > > "Google App Engine" group. > > To post to this group, send email to google-appeng...@googlegroups.com. > > To unsubscribe from this group, send email to > > google-appengine+unsubscr...@googlegroups.com. > > For more options, visit this group > > athttp://groups.google.com/group/google-appengine?hl=en. -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To post to this group, send email to google-appeng...@googlegroups.com. To unsubscribe from this group, send email to google-appengine+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en.
[google-appengine] Re: GAE for CPU intensive time important application
Thanks for the response. Maybe I don't understand something, but why should the 5 second setup on a new instance bother me? A new instance should be created when other instances are near capacity, and not when they exceed it, right? So once initialized it can be "dummy-run" internally and only available 5 seconds later while the existing instance continue to take care of the incoming queries. Also, do you think the latency requirements are realistic with GAE? That is, in the ordinary case, could the response be consistently served back to the querying user with delay of max 3 seconds? On Nov 28, 8:35 am, 风笑雪 wrote: > The White House hosted an online town hall meeting on GAE with GWT, > and received 700 hits per second at its > peak.http://google-code-updates.blogspot.com/2009/04/google-developer-prod... > > But more than 1000 queries a second is never been tested. > > I think Java is not a good choice in your case. When your user > suddenly increasing, starting a new Jave instance may cost more than 5 > seconds, while Python needs less than 1 second. > > 2009/11/27 Eric : > > > > > Hi, > > > I wish to set up a CPU-intensive time-important query service for > > users on the internet. > > Is GAE with Java the right choice? (as compared to other clouds, or > > non-cloud architecture) > > Specifically, in terms of: > > 1) pricing > > 2) latency resulting from slow CPU, JIT compiles, etc.. > > 3) latency resulting from communication of processes inside the cloud > > (e.g. a queuing process and a calculation process) > > 4) latency of communication between cloud and end user > > > A usage scenario I am expecting is: > > - a typical user sends a query (XML of size around 1K) once every 30 > > seconds on average, > > - Each query requires a numerical computation of average time 0.2 sec > > and max time 1 sec (on a 1 GHz Pentium). The computation requires no > > data other than the query itself. > > - The delay a user experiences between sending a query and receiving a > > response should be on average no more than 2 seconds and in general no > > more than 5 seconds. > > - A background save to a DB of the response should occur (not time > > critical) > > - There can be up to 3 simultaneous users - i.e., on average 1000 > > queries a second, each requiring an average 0.2 sec calculation, so > > that would necessitate around 200 CPUs. > > > Is this feasible on GAE Java? > > If so, where can I learn about the correct design methodology for such > > a project on GAE? > > > If this is the wrong forum to ask this, I'd appreciate redirection. > > > Thanks, > > > Eric > > > -- > > > You received this message because you are subscribed to the Google Groups > > "Google App Engine" group. > > To post to this group, send email to google-appeng...@googlegroups.com. > > To unsubscribe from this group, send email to > > google-appengine+unsubscr...@googlegroups.com. > > For more options, visit this group > > athttp://groups.google.com/group/google-appengine?hl=en. -- You received this message because you are subscribed to the Google Groups "Google App Engine" group. To post to this group, send email to google-appeng...@googlegroups.com. To unsubscribe from this group, send email to google-appengine+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/google-appengine?hl=en.
