Chris, Great thanks that is exactly what I was looking for, just to get an idea at this point.
And yes it was for mysql. I was thinking one could create a smarter pool, one that created more connections for sites used more often, and less for others. Much appreciated. On Wed, May 30, 2012 at 10:07 AM, Christopher Schultz < ch...@christopherschultz.net> wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > Ahmed, > > On 5/29/12 9:29 AM, S Ahmed wrote: > > If my requirement for a hosted application is to give each > > customer a separate instance of mysql, I am curious how feasible > > that would be. > > You can certainly do this. > > > What is the memory footprint for a single connection to a > > database? > > That depends a lot of which database you are using (MySQL connections > are fairly modest: the "retained size" of one of my MySQL > JDBC4Connection objects is 66k in an x86-64 environment with a 64-bit > Sun/Oracle JVM), what things you are having cached/pooled on the > client side, etc. You'd have to give us a lot more information about > your environment. Better yet, configure it the way you want it and use > a profiler to see how "big" the connections become. > > > If I had 10K separate mysql instances, would it be feasible to > > create a pool of pools? i.e. a hashmap of connection pools? > > That sounds like a lot of MySQL instances to be contacted by a single > application server. Do you need 10k separate customers all running in > the same webapp? > > If my environment and requirements match yours, you'd need 10000 * > max_pool_size * 66KiB at peak usage. That's about 640MiB for each > connection you want in 10k pools. For a (uniform) max pool size of 4, > you'll need more than 2GiB of heap space just for connection pools. > > Is that acceptable? > > - -chris > -----BEGIN PGP SIGNATURE----- > Version: GnuPG/MacGPG2 v2.0.17 (Darwin) > Comment: GPGTools - http://gpgtools.org > Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ > > iEYEARECAAYFAk/GKb8ACgkQ9CaO5/Lv0PBmCACghH4L1ycmK1UwHHPq1aVu0Sxn > X2IAnjePQzdy5iMAL5pEIe0KgxRY1q8V > =Uieg > -----END PGP SIGNATURE----- > > --------------------------------------------------------------------- > To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org > For additional commands, e-mail: users-h...@tomcat.apache.org > >
