Memcached clients async get usage
Hi, We are planning to use the MemchaheD software and accelerate it with hardware offload. We would like to understand more regarding the general usage scenario with respect to memcached clients. Are async get requests more popular with clients or do they generally wait for response from servers? -- Ravi Shankar JV. -- --- You received this message because you are subscribed to the Google Groups "memcached" group. To unsubscribe from this group and stop receiving emails from it, send an email to memcached+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: memcache memory limit
can anybody tell me how we can decrease the RAM size of MemCached On Friday, 20 March 2009 12:14:25 UTC+5:30, skyhopper wrote: > > Hi > > is there a memory limit for the memcached process ? i want to run it > with -m 4096 option , is that possible ? -- --- You received this message because you are subscribed to the Google Groups "memcached" group. To unsubscribe from this group and stop receiving emails from it, send an email to memcached+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Ordering of commands per connection
HI , We are planning to use the MemchaheD software and accelerate it with hardware offload. We would like to know from protocol prospective each connection should maintain the order in which it receives the command to send a response back ? for Ex: If we receive GET1 GET2 SET1 GET3 do we need to send the response in the same order GET1 GET2 SET1 GET3 . Can we parallelize commands and send them out off order ? Thanks & Regards Ravi G -- --- You received this message because you are subscribed to the Google Groups "memcached" group. To unsubscribe from this group and stop receiving emails from it, send an email to memcached+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Working with memcache and mysql using memcache_functions_mysql UDFs
I have installed the following packages -- 1. libevent-2.0.21 2. memcached-1.4.17 3. libmemcached-0.34 4. memcached_functions_mysql_1.1 All of the above have been installed successfully. The output of the ldconfig -v command (the part where it shows that libmemcached libraries have been included) is as follows: $ldconfig -v /usr/local/libmemcached/lib: libmemcached.so.3 -> libmemcached.so.3.0.0 libmemcachedprotocol.so.0 -> libmemcachedprotocol.so.0.0.0 libmemcachedutil.so.0 -> libmemcachedutil.so.0.0.0 But when I try to load UDF's into mysql using the install_functions.sql that is shipped with memcache_functions it throws the following error: ERROR 1126 (HY000) at line 38: Can't open shared library 'libmemcached_functions_mysql.so' (errno: 0 libmemcached.so.3: cannot open shared object file: No such file or directory) And the contents of the plugin directory are: -rw-r--r-- 1 root root 6.1K Jan 21 13:49 adt_null.so-rw-r--r-- 1 root root 11K Jan 21 13:49 auth.so-rw-r--r-- 1 root root 6.0K Jan 21 13:49 auth_socket.so-rw-r--r-- 1 root root 6.2K Jan 21 13:49 auth_test_plugin.so-rw-r--r-- 1 root root 35K Jan 21 13:49 ha_example.so-rw-r--r-- 1 root root 10K Jan 21 13:49 libdaemon_example.so-rw-r--r-- 1 root root 361K Feb 13 02:47 libmemcached_functions_mysql.a-rwxr-xr-x 1 root root 1.1K Feb 13 02:47 libmemcached_functions_mysql.la-rwxr-xr-x 1 root root 167K Feb 13 02:47 libmemcached_functions_mysql.so-rwxr-xr-x 1 root root 167K Feb 13 02:47 libmemcached_functions_mysql.so.0-rwxr-xr-x 1 root root 167K Feb 13 02:47 libmemcached_functions_mysql.so.0.0.0-rw-r--r-- 1 root root 11K Jan 21 13:49 mypluglib.so-rw-r--r-- 1 root root 5.9K Jan 21 13:49 qa_auth_client.so-rw-r--r-- 1 root root 11K Jan 21 13:49 qa_auth_interface.so-rw-r--r-- 1 root root 6.0K Jan 21 13:49 qa_auth_server.so-rw-r--r-- 1 root root 39K Jan 21 13:49 semisync_master.so-rw-r--r-- 1 root root 15K Jan 21 13:49 semisync_slave.so -- --- You received this message because you are subscribed to the Google Groups "memcached" group. To unsubscribe from this group and stop receiving emails from it, send an email to memcached+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
Sessiom Management
hi, can anyone help me on Advantages with infinispan over EHCache.(EHCache vs infinispan) Thanks in Advance.. -- --- You received this message because you are subscribed to the Google Groups "memcached" group. To unsubscribe from this group and stop receiving emails from it, send an email to memcached+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
Regarding Infinispan Cache Mechanism
hi, Can we use this infinispan in clustered environment. Thanks in Advance... -- --- You received this message because you are subscribed to the Google Groups "memcached" group. To unsubscribe from this group and stop receiving emails from it, send an email to memcached+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
Understanding memcache
hi, can any one help me on how *memcache *useful to us.i mean how and when to use . and also give me some tutorial-links for reference. Thanks in Advance.. -- --- You received this message because you are subscribed to the Google Groups "memcached" group. To unsubscribe from this group and stop receiving emails from it, send an email to memcached+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
Re: PHP and persistent connections
Hey, How did you resolved this...? Need help for the similar issue On Thursday, April 8, 2010 3:14:35 AM UTC+5:30, Jay Paroline wrote: > > This may be due to a basic misunderstanding on my part, but in that > case, if I see lots of entries like this from netstat -tnap running on > the client side, what does it mean? > > tcp0 0 172.16.0.15:35672 > 172.16.0.64:11211 TIME_WAIT - > > 172.16.0.15 is the server I ran netstat -tnap on (the client in this > case) and 172.16.0.64:11211 is the memcache server. > > Jay > > On Apr 7, 4:19 pm, Brian Moon wrote: > > > @Tyn, I'll look into sharing a class instance, didn't know that was > > > possible in APC. > > > > It is not. Well, you can recreate a class, but the connection will not > > be the same. It will have to recreate that resource. > > > > > @Brian Moon, I know the memcache servers can handle having all those > > > incoming connections, I'm just trying to reduce the number of > > > ephemeral ports we need on each web server to handle all the outgoing > > > connections. My understanding is that TIME_WAIT uses up an ephemeral > > > port the same as ESTABLISHED. > > > > TIME_WAIT is a host side state, not client side. > > > > "When you close a socket, the server goes into a TIME_WAIT state, just > > to be really really sure that all the data has gone through." > > > > http://www.unixguide.net/network/socketfaq/2.7.shtml > > > > Brian. > > -- --- You received this message because you are subscribed to the Google Groups "memcached" group. To unsubscribe from this group and stop receiving emails from it, send an email to memcached+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
memcache heartbeat property not working
Hi , I am using xemcached 1.3.8 with repcached replication on it . Inside my code i have set setEnableHeartBeat(false); to false and also i am passing , environment variable through script -Dxmemcached.heartbeat.max.fail.times=2 But still in case if one server is down in cluster , it is continuously trying to connect to that server . please let me know how can i make this try to reconnect only for 2 times .
Memcached client being shutdown if Xmemcached is stopped
I am using xmmecache 1.3.8 version , sometimes in logs i am getting the
below error .
*net.rubyeye.xmemcached.exception.MemcachedException: Xmemcached is stopped*
* at
net.rubyeye.xmemcached.XMemcachedClient.sendCommand(XMemcachedClient.java:247)
*
* at
net.rubyeye.xmemcached.XMemcachedClient.fetch0(XMemcachedClient.java:573)*
* at net.rubyeye.xmemcached.XMemcachedClient.get0(XMemcachedClient.java:971)
*
* at net.rubyeye.xmemcached.XMemcachedClient.gets(XMemcachedClient.java:984)
*
* at
net.rubyeye.xmemcached.XMemcachedClient.gets(XMemcachedClient.java:1006)*
* at net.rubyeye.xmemcached.XMemcachedClient.gets(XMemcachedClient.java:995)
*
This is making the Memcache client shutdown .
Please let me know how to recover from this error
Our code
* private Memcached() throws IOException {*
* String location = ATConfig.getMemcachedLocation();*
* int connCount = 5; *
* MemcachedClientBuilder builder = new XMemcachedClientBuilder(*
* AddrUtil.getAddresses(location));*
* builder.setConnectionPoolSize(connCount);*
* boolean useBinaryProtocl = false;*
* if (useBinaryProtocl) {*
* builder.setCommandFactory(new BinaryCommandFactory());*
* }*
* mcc = builder.build();*
* builder.setSessionLocator(new KetamaMemcachedSessionLocator();*
* mcc.setOpTimeout(5000); *
* }*
Re: How to determine ConnectionPoolSize factor of Memcached for a website
Thanks Henrik for the information . Many users from different forums reported that repcached is good , if they used it with single server (I mean when only 2 severs involved) And i read that using a high connectionpooolsize will result in Wait time out exceptions , so use a low number memcached connection pool size . Please share your views . Thanks in advance . On Sunday, November 11, 2012 10:26:45 PM UTC+5:30, Henrik Schröder wrote: > > 1) DO NOT use Memcached as a datastore. It is a cache. You can not > reliably store data in it. > > 2) Your solution with a load balancer and repcached is EXTREMELY WEIRD. > Best practice is to just use the servers straight up and letting the > clients choose which server to store their data on. With your current > solution, adding a memcached server will affect the performance of the app > negatively, thereby completely eliminating the linear scalability of > memcached, which is the whole purpose of the technology in the first place. > > 3) How on earth do you suppose that people on a mailing list would be able > to accurately guess the optimal parameters for your connection pool, > without knowing anything about the traffic patterns of your app? BENCHMARK > it yourself, simulate your 700 users, test different connection pool sizes, > and pick the one that's performing the best. > > 4) Try 17. That's a cute number. It should work just as well as any other > number for your connection pool size for your app. > > > /Henrik > > > On Sun, Nov 11, 2012 at 6:51 AM, Ravi >wrote: > >> Hi , >> >> We are using Memcache as a dataStore for our high traffic web site .Under >> which there may be 700 concurrent users at a time . >> >> Our set is that , there are six web servers in front , controlled by a >> Load Balancer hitting two Mmecache servers which are in cluster . >> * >> * >> *String location = server1:11211 server2:11211 * >> *MemcachedClientBuilder builder = new >> XMemcachedClientBuilder(AddrUtil.getAddresses(location));* >> *builder.setConnectionPoolSize(5);* >> >> >> Till now i am using the setConnectionPoolSize to 5 . >> >> My questions are >> >> 1. Is setting ConnectionPoolSize to 5 is correct in my case ?? >> 2. Is setting ConnectionPoolSize factor impacts the application >> performance anyway . >> >> >> >> >> >> >> >> >
How to determine ConnectionPoolSize factor of Memcached for a website
Hi , We are using Memcache as a dataStore for our high traffic web site .Under which there may be 700 concurrent users at a time . Our set is that , there are six web servers in front , controlled by a Load Balancer hitting two Mmecache servers which are in cluster . * * *String location = server1:11211 server2:11211 * *MemcachedClientBuilder builder = new XMemcachedClientBuilder(AddrUtil.getAddresses(location));* *builder.setConnectionPoolSize(5);* Till now i am using the setConnectionPoolSize to 5 . My questions are 1. Is setting ConnectionPoolSize to 5 is correct in my case ?? 2. Is setting ConnectionPoolSize factor impacts the application performance anyway .
How is it possible to locate server based on key hash code
I have 3 Memcached balanced Servers running for the Application . I googled and found out that , using hashkey , its possible to locate a key from any of the server I am using KetamaMemcachedSessionLocator set up with my code . I tried this way , but i am not sure if its correct or not . int mod = MemcachedClient.getAvailableServers().size(); // This value is 3 int keyid = key.hashCode(); COuld anybody please tell me how can i locate first , Second Server with this approach ??
Re: Quick question on the Timezone
I guess, I did not phrase my question correctly to begin with. Changing the server time from EST based to UTC based will probably expire all the items immediately as UTC offsets the time by ( -X hours). Thanks, Ravi. On Wed, Sep 22, 2010 at 2:08 PM, Brian Moon wrote: > On 9/22/10 4:03 PM, Matt Ingenthron wrote: >> >> On 9/22/10 1:41 PM, Ravi Chittari wrote: >>> >>> We have memcached instances up and running in production. We want to >>> change our systems from one timezone ( Say EST) to UTC. >>> Does memcached instance automatically pick up new Timezone and what >>> happens to the cached items? >> >> IIRC, times are tracked as relative to the local clock, so if you change >> the system clock things will either expire late or early. It's probably >> best to restart the cache server for this sort of thing. > > But, changing the system clock is not the same as changing the time zone. > Time zones are only a formatting thing. A point in time is the same no > matter what the time zone. > > -- > > Brian. > > http://brian.moonspot.net/ >
Quick question on the Timezone
We have memcached instances up and running in production. We want to change our systems from one timezone ( Say EST) to UTC. Does memcached instance automatically pick up new Timezone and what happens to the cached items? Thanks, Ravi.
multiple instance running on server with bound same port and different IP's
Hi, Is there any way to run multiple instance running on one single server with bound same port and different IP's , as I know it is not possible but any patch or anything new code that can be implement on it. I need the same port running on different IP's , can any one help out on this. Ravi
Re: need help with Object too large for cache issue
we are in the midst of upgrading to 1.4.2.. It will happen in a week or so. we already upgraded our staging and qa env with this and moving to production shortly. On Fri, Oct 30, 2009 at 2:22 PM, Dustin wrote: > > > On Oct 30, 9:55 am, Ravi Chittari wrote: > > > I am using memacached 1.2.2 > > This version is *very* old, BTW. I'd strongly recommend upgrading.
Re: need help with Object too large for cache issue
Thanks Brian.. When this error happens.. it takes 3 seconds for the server to respond.. are there any timeouts etc ? 3secs is quite a long time. Thanks, Ravi. On Fri, Oct 30, 2009 at 1:19 PM, Brian Hawkins wrote: > The limit is 1 meg. Try serializing the object to file to see how big it > is. You can use a Different serialization method to make it smaller. > > Brian > > > On Fri, Oct 30, 2009 at 10:55 AM, Ravi Chittari wrote: > >> I am seeing two errors in my logs >> >> 2009-10-30 12:43:45,468 ERROR [com.danga.MemCached.MemCachedClient] >> error storing data in cache for key:sessionkey, $Version -- length: 368 >> 2009-10-30 12:43:45,469 ERROR [com.danga.MemCached.MemCachedClient] >> server response: SERVER_ERROR object too large for cache >> >> I am using memacached 1.2.2 >> >> What is the max limit of the object that can be stored.. I am just trying >> to store a serialized Map.. I know it is not a big size of a map or anything >> like that. >> >> (a) How can I print more verbose logs? >> (b) Where can I find the limits for the version I am using? i.e object >> sizes I can store etc. >> >> Thanks, >> >> >
need help with Object too large for cache issue
I am seeing two errors in my logs 2009-10-30 12:43:45,468 ERROR [com.danga.MemCached.MemCachedClient] error storing data in cache for key:sessionkey, $Version -- length: 368 2009-10-30 12:43:45,469 ERROR [com.danga.MemCached.MemCachedClient] server response: SERVER_ERROR object too large for cache I am using memacached 1.2.2 What is the max limit of the object that can be stored.. I am just trying to store a serialized Map.. I know it is not a big size of a map or anything like that. (a) How can I print more verbose logs? (b) Where can I find the limits for the version I am using? i.e object sizes I can store etc. Thanks,
Re: memcached hangs suddenly and slows down
Thanks Edward.. One last question. Actually the version we are using is 1.2.2, I believe 1.2.2 has similar issues as 1.2.5. You think 1.2.2 has similar issues as 1.2.5? is 1.2.8 stable version but less features than 1.4.1? Thanks, Ravi. On Sat, Oct 3, 2009 at 5:23 PM, dormando wrote: > Please upgrade; version 1.2.5 has a number of spin/crash bugs that have > since been fixed. > > We highly recommend 1.4.1, but 1.2.8 is still available. > > -Dormando > > On Sat, 3 Oct 2009, Ravi Chittari wrote: > > > > > Version is 1.2.5 > > > > memcached -d -m 256 > > it is not going into swap or anything like that. It has an 8GB RAM, the > total RAM used up is 5GB for other apps. > > > > But when it hangs, I see that cpu is 100% and memcached is using up the > cpu. > > > > Thanks, > > Ravi. > > > > On Fri, Oct 2, 2009 at 6:46 PM, dormando wrote: > > > > Hey, > > > > What version are you on? > > > > Is the machine it's on swapping? how much memory is free? cpu free? > what's > > the general load on the box? > > > > What's the commandline you're using to start memcached? > > > > -Dormando > > > > On Fri, 2 Oct 2009, rch wrote: > > > > > > > > I am using memcached in my production environment. > > > It works fine 90% of the time. > > > But suddenly, it slows down. when I try to connect via telnet the > > > connect part is slow. > > > How can I debug this? > > > > > > Also one more thing that is not clear is, stats shows the current > > > connections more than 1024. I am starting memcached with default > > > settings. so, I thought max connections that should be allowed are > > > 1024. But I see below.. which is strange. > > > > > > STAT curr_connections 1063 > > > STAT total_connections 79538 > > > STAT connection_structures 1092 > > > > > > At this time the server is responding fine. Why am I seeing more than > > > 1024 in current connections? > > > > > > > > > > > > > > > > > > > > > > > >
Re: memcached hangs suddenly and slows down
Version is 1.2.5 memcached -d -m 256 it is not going into swap or anything like that. It has an 8GB RAM, the total RAM used up is 5GB for other apps. But when it hangs, I see that cpu is 100% and memcached is using up the cpu. Thanks, Ravi. On Fri, Oct 2, 2009 at 6:46 PM, dormando wrote: > > Hey, > > What version are you on? > > Is the machine it's on swapping? how much memory is free? cpu free? what's > the general load on the box? > > What's the commandline you're using to start memcached? > > -Dormando > > On Fri, 2 Oct 2009, rch wrote: > > > > > I am using memcached in my production environment. > > It works fine 90% of the time. > > But suddenly, it slows down. when I try to connect via telnet the > > connect part is slow. > > How can I debug this? > > > > Also one more thing that is not clear is, stats shows the current > > connections more than 1024. I am starting memcached with default > > settings. so, I thought max connections that should be allowed are > > 1024. But I see below.. which is strange. > > > > STAT curr_connections 1063 > > STAT total_connections 79538 > > STAT connection_structures 1092 > > > > At this time the server is responding fine. Why am I seeing more than > > 1024 in current connections? > > > > > > > > > > >
Re: memcached hangs suddenly and slows down
Thanks Edward. I do get an alarm when things are bad on the memcached. But the issue I want to figure out is, why and how it got itself into a bad state. Do you suggest turning on the debug logs? >>>>Out Of Memory errors. >>>>Time out on connect. >>>>No Connect. >>>>After a few week of looking at the issues, I can get all of these >>>>issues fixed and the code works great. Where are your fixes going? on the client side or on the server side? Thanks, Ravi. On Fri, Oct 2, 2009 at 4:57 PM, Edward M. Goldberg < edwardmgoldb...@gmail.com> wrote: > > Well I see that you are not getting lots of replies so I will step in. > > What I do is run a small CRON job that does a few Memcache actions > like: > > Set key > Get key > Get status > > And watch the output for issues on each server. I use plain commands > like: > > echo "stats" | nc localhost 11211 > > This way I see all of the interaction with no client software in the > way. > > When an error shows up in these simple commands I send an Alert to the > RightScale Monitor System I use. > > You may have a Munin or other monitor system. > > Now I see the exact moment when the Memcached goes sour. This > provides a big hint as to why it is happening. > > Issues I see are: > > Out Of Memory errors. > Time out on connect. > No Connect. > > After a few week of looking at the issues, I can get all of these > issues fixed and the code works great. > > It does take a few hits at first to find issues like DNS falures, Set > up values set too low. > > Please ask for help, Memcache is a great Cache > > Edward M. Goldberg > http://myCloudWatcher.com/ >
Re: memcached hangs suddenly and slows down
Any one who can help on this? On Fri, Oct 2, 2009 at 8:43 AM, rch wrote: > I am using memcached in my production environment. > It works fine 90% of the time. > But suddenly, it slows down. when I try to connect via telnet the > connect part is slow. > How can I debug this? > > Also one more thing that is not clear is, stats shows the current > connections more than 1024. I am starting memcached with default > settings. so, I thought max connections that should be allowed are > 1024. But I see below.. which is strange. > > STAT curr_connections 1063 > STAT total_connections 79538 > STAT connection_structures 1092 > > At this time the server is responding fine. Why am I seeing more than > 1024 in current connections? > > > > >
Re: problem of sync
I have two data centers with 2 hosts on each center. Keeping latest data on memcached cluster across 4 hosts for inserting app. In case of failure of 1 host on either data center, complete data set should be available for query clients. Any thoughts to implement 4 hosts cluster with repcached master slave config. On Jan 23, 1:57 pm, Dustin wrote: > On Jan 23, 8:25 am, Ravi wrote: > > > Any strategy for using repcached for more than 2 servers. > > What is your goal when you replicate cache to even one other server?
Re: problem of sync
Any strategy for using repcached for more than 2 servers. On Jan 5, 9:25 pm, "Dean Harding" wrote: > > I configure lvs use "round-robin" policy. > > > s1 has apache and memcached, > > s2 has apache and memcached. > > And apache on s1 use memcached on s1, apache on s2 use memcached on s2. > > And s1 and s2 use a same database. > > > There is a problem: > > Users could not upload files sometimes. > > But there is no problem, after I let the two apaches to use a same > > memcached. > > Yes, that's pretty much how it should work - both instances of apache use > BOTH instances of memcache. > > All memcached clients need to have *exactly* the same configuration for it to > all work. That means if you have memcached on server A and server B, then ALL > clients need to point to BOTH A AND B. If you point some to A and some to B, > then you're going to get weird stuff happening. > > Memcached is not magic, it only does what you tell it to do. > > Dean.
