Re: Dogpile effect with Varnish?
Hi Ben, Thanks a lot for your answers! I'm looking forward to reading you about the other thread. Thanks! Thomas. On Wed, Oct 13, 2010 at 11:40 PM, Ben Scofield b...@heroku.com wrote: Sorry for the delay! I finally talked to our Varnish expert, and he confirmed that: 1) our configuration should not impede Varnish's default behavior (re: the first question in this thread), and 2) your app's resource configuration (# of dynos, etc.) doesn't affect how much traffic Varnish can handle for it. Our best estimate for Varnish's capacity for a single cached URL is on the order of 4000 requests/second, sustained. I haven't dug deeply into your other thread yet, Thomas -- I'll take another look at it when I can. Ben On Oct 12, 11:13 am, Thomas Balthazar gro...@suitmymind.com wrote: Hi Ben, Any update about this? Thanks, Thomas. On Tue, Oct 5, 2010 at 8:33 PM, Thomas Balthazar gro...@suitmymind.com wrote: Hello Ben, I just read you were about to talk to the Varnish specialist at Heroku. I would really appreciate if you took the time to help me to find the answer to those 2 unanswered questions about Varnish and caching : http://groups.google.com/group/heroku/browse_thread/thread/8e39658d53... http://groups.google.com/group/heroku/browse_thread/thread/fd23e886c2... Thanks in advance for your help! Thomas. On Tue, Oct 5, 2010 at 7:52 PM, Ben Scofield b...@heroku.com wrote: Not sure why this didn't come through earlier, but: I tried out a few experiments, and it looks like our setup doesn't interfere with this default behavior. I'm going to talk to someone with more intimate knowledge of our Varnish config to confirm that, but so far it looks promising. Ben On Oct 5, 12:00 pm, Chris Hanks christopher.m.ha...@gmail.com wrote: Is anyone from Heroku around that might know how their setup works? On Oct 2, 8:42 pm, Chris Hanks christopher.m.ha...@gmail.com wrote: I'm wondering about Heroku's use of Varnish. Suppose I have a page that is expensive to produce (lots of database queries) but can be cached in Varnish. Right after Varnish's copy expires, if it's very popular, I might have a dozen people accessing it simultaneously before the newly created version can be stashed in Varnish. So, based on a thread I found (http://www.gossamer-threads.com/lists/ varnish/misc/14750) it looks like Varnish is smart enough by default to only send that expensive request to my backend once, and serve up the response to all the people waiting for it (to prevent a dogpiling effect). But I know that Heroku has its own configuration for Varnish (with lots of servers in a hash ring), and I was wondering whether it's still set up to do this. Thanks! -- You received this message because you are subscribed to the Google Groups Heroku group. To post to this group, send email to her...@googlegroups.com. To unsubscribe from this group, send email to heroku+unsubscr...@googlegroups.com. For more options, visit this group athttp://groups.google.com/group/heroku?hl=en. -- You received this message because you are subscribed to the Google Groups Heroku group. To post to this group, send email to her...@googlegroups.com. To unsubscribe from this group, send email to heroku+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/heroku?hl=en. -- You received this message because you are subscribed to the Google Groups Heroku group. To post to this group, send email to her...@googlegroups.com. To unsubscribe from this group, send email to heroku+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/heroku?hl=en.
Re: Dogpile effect with Varnish?
Sorry for the delay! I finally talked to our Varnish expert, and he confirmed that: 1) our configuration should not impede Varnish's default behavior (re: the first question in this thread), and 2) your app's resource configuration (# of dynos, etc.) doesn't affect how much traffic Varnish can handle for it. Our best estimate for Varnish's capacity for a single cached URL is on the order of 4000 requests/second, sustained. I haven't dug deeply into your other thread yet, Thomas -- I'll take another look at it when I can. Ben On Oct 12, 11:13 am, Thomas Balthazar gro...@suitmymind.com wrote: Hi Ben, Any update about this? Thanks, Thomas. On Tue, Oct 5, 2010 at 8:33 PM, Thomas Balthazar gro...@suitmymind.com wrote: Hello Ben, I just read you were about to talk to the Varnish specialist at Heroku. I would really appreciate if you took the time to help me to find the answer to those 2 unanswered questions about Varnish and caching : http://groups.google.com/group/heroku/browse_thread/thread/8e39658d53... http://groups.google.com/group/heroku/browse_thread/thread/fd23e886c2... Thanks in advance for your help! Thomas. On Tue, Oct 5, 2010 at 7:52 PM, Ben Scofield b...@heroku.com wrote: Not sure why this didn't come through earlier, but: I tried out a few experiments, and it looks like our setup doesn't interfere with this default behavior. I'm going to talk to someone with more intimate knowledge of our Varnish config to confirm that, but so far it looks promising. Ben On Oct 5, 12:00 pm, Chris Hanks christopher.m.ha...@gmail.com wrote: Is anyone from Heroku around that might know how their setup works? On Oct 2, 8:42 pm, Chris Hanks christopher.m.ha...@gmail.com wrote: I'm wondering about Heroku's use of Varnish. Suppose I have a page that is expensive to produce (lots of database queries) but can be cached in Varnish. Right after Varnish's copy expires, if it's very popular, I might have a dozen people accessing it simultaneously before the newly created version can be stashed in Varnish. So, based on a thread I found (http://www.gossamer-threads.com/lists/ varnish/misc/14750) it looks like Varnish is smart enough by default to only send that expensive request to my backend once, and serve up the response to all the people waiting for it (to prevent a dogpiling effect). But I know that Heroku has its own configuration for Varnish (with lots of servers in a hash ring), and I was wondering whether it's still set up to do this. Thanks! -- You received this message because you are subscribed to the Google Groups Heroku group. To post to this group, send email to her...@googlegroups.com. To unsubscribe from this group, send email to heroku+unsubscr...@googlegroups.com. For more options, visit this group athttp://groups.google.com/group/heroku?hl=en. -- You received this message because you are subscribed to the Google Groups Heroku group. To post to this group, send email to her...@googlegroups.com. To unsubscribe from this group, send email to heroku+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/heroku?hl=en.
Re: Dogpile effect with Varnish?
Thanks, Ben! On Oct 13, 2:40 pm, Ben Scofield b...@heroku.com wrote: Sorry for the delay! I finally talked to our Varnish expert, and he confirmed that: 1) our configuration should not impede Varnish's default behavior (re: the first question in this thread), and 2) your app's resource configuration (# of dynos, etc.) doesn't affect how much traffic Varnish can handle for it. Our best estimate for Varnish's capacity for a single cached URL is on the order of 4000 requests/second, sustained. I haven't dug deeply into your other thread yet, Thomas -- I'll take another look at it when I can. Ben On Oct 12, 11:13 am, Thomas Balthazar gro...@suitmymind.com wrote: Hi Ben, Any update about this? Thanks, Thomas. On Tue, Oct 5, 2010 at 8:33 PM, Thomas Balthazar gro...@suitmymind.com wrote: Hello Ben, I just read you were about to talk to the Varnish specialist at Heroku. I would really appreciate if you took the time to help me to find the answer to those 2 unanswered questions about Varnish and caching : http://groups.google.com/group/heroku/browse_thread/thread/8e39658d53... http://groups.google.com/group/heroku/browse_thread/thread/fd23e886c2... Thanks in advance for your help! Thomas. On Tue, Oct 5, 2010 at 7:52 PM, Ben Scofield b...@heroku.com wrote: Not sure why this didn't come through earlier, but: I tried out a few experiments, and it looks like our setup doesn't interfere with this default behavior. I'm going to talk to someone with more intimate knowledge of our Varnish config to confirm that, but so far it looks promising. Ben On Oct 5, 12:00 pm, Chris Hanks christopher.m.ha...@gmail.com wrote: Is anyone from Heroku around that might know how their setup works? On Oct 2, 8:42 pm, Chris Hanks christopher.m.ha...@gmail.com wrote: I'm wondering about Heroku's use of Varnish. Suppose I have a page that is expensive to produce (lots of database queries) but can be cached in Varnish. Right after Varnish's copy expires, if it's very popular, I might have a dozen people accessing it simultaneously before the newly created version can be stashed in Varnish. So, based on a thread I found (http://www.gossamer-threads.com/lists/ varnish/misc/14750) it looks like Varnish is smart enough by default to only send that expensive request to my backend once, and serve up the response to all the people waiting for it (to prevent a dogpiling effect). But I know that Heroku has its own configuration for Varnish (with lots of servers in a hash ring), and I was wondering whether it's still set up to do this. Thanks! -- You received this message because you are subscribed to the Google Groups Heroku group. To post to this group, send email to her...@googlegroups.com. To unsubscribe from this group, send email to heroku+unsubscr...@googlegroups.com. For more options, visit this group athttp://groups.google.com/group/heroku?hl=en. -- You received this message because you are subscribed to the Google Groups Heroku group. To post to this group, send email to her...@googlegroups.com. To unsubscribe from this group, send email to heroku+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/heroku?hl=en.
Re: Dogpile effect with Varnish?
Hi Ben, Any update about this? Thanks, Thomas. On Tue, Oct 5, 2010 at 8:33 PM, Thomas Balthazar gro...@suitmymind.com wrote: Hello Ben, I just read you were about to talk to the Varnish specialist at Heroku. I would really appreciate if you took the time to help me to find the answer to those 2 unanswered questions about Varnish and caching : http://groups.google.com/group/heroku/browse_thread/thread/8e39658d53c53b7c http://groups.google.com/group/heroku/browse_thread/thread/fd23e886c24131b3 Thanks in advance for your help! Thomas. On Tue, Oct 5, 2010 at 7:52 PM, Ben Scofield b...@heroku.com wrote: Not sure why this didn't come through earlier, but: I tried out a few experiments, and it looks like our setup doesn't interfere with this default behavior. I'm going to talk to someone with more intimate knowledge of our Varnish config to confirm that, but so far it looks promising. Ben On Oct 5, 12:00 pm, Chris Hanks christopher.m.ha...@gmail.com wrote: Is anyone from Heroku around that might know how their setup works? On Oct 2, 8:42 pm, Chris Hanks christopher.m.ha...@gmail.com wrote: I'm wondering about Heroku's use of Varnish. Suppose I have a page that is expensive to produce (lots of database queries) but can be cached in Varnish. Right after Varnish's copy expires, if it's very popular, I might have a dozen people accessing it simultaneously before the newly created version can be stashed in Varnish. So, based on a thread I found (http://www.gossamer-threads.com/lists/ varnish/misc/14750) it looks like Varnish is smart enough by default to only send that expensive request to my backend once, and serve up the response to all the people waiting for it (to prevent a dogpiling effect). But I know that Heroku has its own configuration for Varnish (with lots of servers in a hash ring), and I was wondering whether it's still set up to do this. Thanks! -- You received this message because you are subscribed to the Google Groups Heroku group. To post to this group, send email to her...@googlegroups.com. To unsubscribe from this group, send email to heroku+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/heroku?hl=en. -- You received this message because you are subscribed to the Google Groups Heroku group. To post to this group, send email to her...@googlegroups.com. To unsubscribe from this group, send email to heroku+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/heroku?hl=en.
Re: Dogpile effect with Varnish?
Thanks for looking into this stuff, Ben. On Oct 5, 11:33 am, Thomas Balthazar gro...@suitmymind.com wrote: Hello Ben, I just read you were about to talk to the Varnish specialist at Heroku. I would really appreciate if you took the time to help me to find the answer to those 2 unanswered questions about Varnish and caching :http://groups.google.com/group/heroku/browse_thread/thread/8e39658d53...http://groups.google.com/group/heroku/browse_thread/thread/fd23e886c2... Thanks in advance for your help! Thomas. On Tue, Oct 5, 2010 at 7:52 PM, Ben Scofield b...@heroku.com wrote: Not sure why this didn't come through earlier, but: I tried out a few experiments, and it looks like our setup doesn't interfere with this default behavior. I'm going to talk to someone with more intimate knowledge of our Varnish config to confirm that, but so far it looks promising. Ben On Oct 5, 12:00 pm, Chris Hanks christopher.m.ha...@gmail.com wrote: Is anyone from Heroku around that might know how their setup works? On Oct 2, 8:42 pm, Chris Hanks christopher.m.ha...@gmail.com wrote: I'm wondering about Heroku's use of Varnish. Suppose I have a page that is expensive to produce (lots of database queries) but can be cached in Varnish. Right after Varnish's copy expires, if it's very popular, I might have a dozen people accessing it simultaneously before the newly created version can be stashed in Varnish. So, based on a thread I found (http://www.gossamer-threads.com/lists/ varnish/misc/14750) it looks like Varnish is smart enough by default to only send that expensive request to my backend once, and serve up the response to all the people waiting for it (to prevent a dogpiling effect). But I know that Heroku has its own configuration for Varnish (with lots of servers in a hash ring), and I was wondering whether it's still set up to do this. Thanks! -- You received this message because you are subscribed to the Google Groups Heroku group. To post to this group, send email to her...@googlegroups.com. To unsubscribe from this group, send email to heroku+unsubscr...@googlegroups.com. For more options, visit this group athttp://groups.google.com/group/heroku?hl=en. -- You received this message because you are subscribed to the Google Groups Heroku group. To post to this group, send email to her...@googlegroups.com. To unsubscribe from this group, send email to heroku+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/heroku?hl=en.
Re: Dogpile effect with Varnish?
Is anyone from Heroku around that might know how their setup works? On Oct 2, 8:42 pm, Chris Hanks christopher.m.ha...@gmail.com wrote: I'm wondering about Heroku's use of Varnish. Suppose I have a page that is expensive to produce (lots of database queries) but can be cached in Varnish. Right after Varnish's copy expires, if it's very popular, I might have a dozen people accessing it simultaneously before the newly created version can be stashed in Varnish. So, based on a thread I found (http://www.gossamer-threads.com/lists/ varnish/misc/14750) it looks like Varnish is smart enough by default to only send that expensive request to my backend once, and serve up the response to all the people waiting for it (to prevent a dogpiling effect). But I know that Heroku has its own configuration for Varnish (with lots of servers in a hash ring), and I was wondering whether it's still set up to do this. Thanks! -- You received this message because you are subscribed to the Google Groups Heroku group. To post to this group, send email to her...@googlegroups.com. To unsubscribe from this group, send email to heroku+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/heroku?hl=en.
Re: Dogpile effect with Varnish?
Hi Chris, I just did some quick tests, and it looks like Varnish is behaving as advertised -- expensive requests are only sent to the backend once. I'm going to confirm those experimental results with someone who knows more about the configuration, but you should be good to go. Ben On Oct 5, 12:00 pm, Chris Hanks christopher.m.ha...@gmail.com wrote: Is anyone from Heroku around that might know how their setup works? On Oct 2, 8:42 pm, Chris Hanks christopher.m.ha...@gmail.com wrote: I'm wondering about Heroku's use of Varnish. Suppose I have a page that is expensive to produce (lots of database queries) but can be cached in Varnish. Right after Varnish's copy expires, if it's very popular, I might have a dozen people accessing it simultaneously before the newly created version can be stashed in Varnish. So, based on a thread I found (http://www.gossamer-threads.com/lists/ varnish/misc/14750) it looks like Varnish is smart enough by default to only send that expensive request to my backend once, and serve up the response to all the people waiting for it (to prevent a dogpiling effect). But I know that Heroku has its own configuration for Varnish (with lots of servers in a hash ring), and I was wondering whether it's still set up to do this. Thanks! -- You received this message because you are subscribed to the Google Groups Heroku group. To post to this group, send email to her...@googlegroups.com. To unsubscribe from this group, send email to heroku+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/heroku?hl=en.
Re: Dogpile effect with Varnish?
Not sure why this didn't come through earlier, but: I tried out a few experiments, and it looks like our setup doesn't interfere with this default behavior. I'm going to talk to someone with more intimate knowledge of our Varnish config to confirm that, but so far it looks promising. Ben On Oct 5, 12:00 pm, Chris Hanks christopher.m.ha...@gmail.com wrote: Is anyone from Heroku around that might know how their setup works? On Oct 2, 8:42 pm, Chris Hanks christopher.m.ha...@gmail.com wrote: I'm wondering about Heroku's use of Varnish. Suppose I have a page that is expensive to produce (lots of database queries) but can be cached in Varnish. Right after Varnish's copy expires, if it's very popular, I might have a dozen people accessing it simultaneously before the newly created version can be stashed in Varnish. So, based on a thread I found (http://www.gossamer-threads.com/lists/ varnish/misc/14750) it looks like Varnish is smart enough by default to only send that expensive request to my backend once, and serve up the response to all the people waiting for it (to prevent a dogpiling effect). But I know that Heroku has its own configuration for Varnish (with lots of servers in a hash ring), and I was wondering whether it's still set up to do this. Thanks! -- You received this message because you are subscribed to the Google Groups Heroku group. To post to this group, send email to her...@googlegroups.com. To unsubscribe from this group, send email to heroku+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/heroku?hl=en.
Re: Dogpile effect with Varnish?
Hello Ben, I just read you were about to talk to the Varnish specialist at Heroku. I would really appreciate if you took the time to help me to find the answer to those 2 unanswered questions about Varnish and caching : http://groups.google.com/group/heroku/browse_thread/thread/8e39658d53c53b7c http://groups.google.com/group/heroku/browse_thread/thread/fd23e886c24131b3 Thanks in advance for your help! Thomas. On Tue, Oct 5, 2010 at 7:52 PM, Ben Scofield b...@heroku.com wrote: Not sure why this didn't come through earlier, but: I tried out a few experiments, and it looks like our setup doesn't interfere with this default behavior. I'm going to talk to someone with more intimate knowledge of our Varnish config to confirm that, but so far it looks promising. Ben On Oct 5, 12:00 pm, Chris Hanks christopher.m.ha...@gmail.com wrote: Is anyone from Heroku around that might know how their setup works? On Oct 2, 8:42 pm, Chris Hanks christopher.m.ha...@gmail.com wrote: I'm wondering about Heroku's use of Varnish. Suppose I have a page that is expensive to produce (lots of database queries) but can be cached in Varnish. Right after Varnish's copy expires, if it's very popular, I might have a dozen people accessing it simultaneously before the newly created version can be stashed in Varnish. So, based on a thread I found (http://www.gossamer-threads.com/lists/ varnish/misc/14750) it looks like Varnish is smart enough by default to only send that expensive request to my backend once, and serve up the response to all the people waiting for it (to prevent a dogpiling effect). But I know that Heroku has its own configuration for Varnish (with lots of servers in a hash ring), and I was wondering whether it's still set up to do this. Thanks! -- You received this message because you are subscribed to the Google Groups Heroku group. To post to this group, send email to her...@googlegroups.com. To unsubscribe from this group, send email to heroku+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/heroku?hl=en. -- You received this message because you are subscribed to the Google Groups Heroku group. To post to this group, send email to her...@googlegroups.com. To unsubscribe from this group, send email to heroku+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/heroku?hl=en.
Dogpile effect with Varnish?
I'm wondering about Heroku's use of Varnish. Suppose I have a page that is expensive to produce (lots of database queries) but can be cached in Varnish. Right after Varnish's copy expires, if it's very popular, I might have a dozen people accessing it simultaneously before the newly created version can be stashed in Varnish. So, based on a thread I found (http://www.gossamer-threads.com/lists/ varnish/misc/14750) it looks like Varnish is smart enough by default to only send that expensive request to my backend once, and serve up the response to all the people waiting for it (to prevent a dogpiling effect). But I know that Heroku has its own configuration for Varnish (with lots of servers in a hash ring), and I was wondering whether it's still set up to do this. Thanks! -- You received this message because you are subscribed to the Google Groups Heroku group. To post to this group, send email to her...@googlegroups.com. To unsubscribe from this group, send email to heroku+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/heroku?hl=en.
