Re: Memcached repcached
Hi Pratibha, if you need replication i have written memcached-like server which supports same operations, plus it has built-in replication and snapshots based on MVCC. Basically it works the same way but algorithms are different (main point is when there are large differences between TTLs of keys it'll use much less memory because it keeps expiration times in separated memory area and reclaim algorithm works totally differently). https://github.com/slawomir-pryczek/FlatDB/blob/master/REPLICATION.md Currently connector for PHP is written, but should be easy to port it to other languages as it's very simple, based on persistent sockets (like 200 lines of code). Using it on production for like 4 years and trying to get some more users, so you can check it out :) So that's not like memcached driver, just something if you need replicated K/V store which is compatible with memcached (compatible = supports same operations, not has same protocol) W dniu środa, 15 kwietnia 2020 10:03:23 UTC+2 użytkownik pratibha sharma Jagnere napisał: > > Hi, > > has anyone used repcached package recently. > I am trying to setup but when I run the memcached service, I am getting > segmentation fault. > > Is there any other alternative? > -- --- 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. To view this discussion on the web visit https://groups.google.com/d/msgid/memcached/5a81dfc9-9ae5-4cda-b469-009612d2319f%40googlegroups.com.
Re: Memcached repcached
Sorry, there's no support for repcached. On Wed, 15 Apr 2020, pratibha sharma Jagnere wrote: > Hi, > has anyone used repcached package recently. > I am trying to setup but when I run the memcached service, I am getting > segmentation fault. > > Is there any other alternative? > > -- > > --- > 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. > To view this discussion on the web visit > https://groups.google.com/d/msgid/memcached/4f6bd405-fa9a-4e27-ba19-689dbe2b2040%40googlegroups.com. > > -- --- 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. To view this discussion on the web visit https://groups.google.com/d/msgid/memcached/alpine.DEB.2.21.2004151422060.23694%40dskull.
Re: CAS-SSO , Memcached-Repcached TGT replication issue
Hi, I am trying to setup repcached on CentOS for memcached 1.4.15 but it is giving segmentation fault. May be something in my setup is not configured correctly. Can you help me with the steps you did to set it up? Also which OS version are you running? Regards Pratibha On Thursday, 5 November 2015 01:07:14 UTC+8, Said Ramli wrote: > > Hello , > > I'm running into a new issue with HA jasig Cas configuration : > > CAS 4.0.6 > > cas-server-integration-memcached 4.0.6 > memecached : 1.4.13 > repcached : 2.3.1 > > I have 2 memcached instances with repcached installation , when I test the > replication using telnet command line it looks like good in 2 directions , > but when I try to make everything up by connecting me to my CAS server , it > creates and add TGT ticket into one server succesfully , BUT the > replication to the other server is not performed !!! > > I still retrieve my TGT ticket in one server and I can't in the other one. > > Any help pleaze , I m blocked ! > > Thx for 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. To view this discussion on the web visit https://groups.google.com/d/msgid/memcached/287b0dd3-ec47-4957-9f76-ab9349053bc1%40googlegroups.com.
Memcached repcached
Hi, has anyone used repcached package recently. I am trying to setup but when I run the memcached service, I am getting segmentation fault. Is there any other alternative? -- --- 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. To view this discussion on the web visit https://groups.google.com/d/msgid/memcached/4f6bd405-fa9a-4e27-ba19-689dbe2b2040%40googlegroups.com.
Re: CAS-SSO , Memcached-Repcached TGT replication issue
Hi , It was about a bug into net.spy.memcached.MemcachedNode.isActive() The first invocation of this method just after shutting down the memcached server , returns true !!! and then the operation crach ... Fixed by a workaround solution.. BR Le mercredi 4 novembre 2015 17:07:14 UTC, Said Ramli a écrit : > > Hello , > > I'm running into a new issue with HA jasig Cas configuration : > > CAS 4.0.6 > > cas-server-integration-memcached 4.0.6 > memecached : 1.4.13 > repcached : 2.3.1 > > I have 2 memcached instances with repcached installation , when I test the > replication using telnet command line it looks like good in 2 directions , > but when I try to make everything up by connecting me to my CAS server , it > creates and add TGT ticket into one server succesfully , BUT the > replication to the other server is not performed !!! > > I still retrieve my TGT ticket in one server and I can't in the other one. > > Any help pleaze , I m blocked ! > > Thx for 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/d/optout.
CAS-SSO , Memcached-Repcached TGT replication issue
Hello , I'm running into a new issue with HA jasig Cas configuration : CAS 4.0.6 cas-server-integration-memcached 4.0.6 memecached : 1.4.13 repcached : 2.3.1 I have 2 memcached instances with repcached installation , when I test the replication using telnet command line it looks like good in 2 directions , but when I try to make everything up by connecting me to my CAS server , it creates and add TGT ticket into one server succesfully , BUT the replication to the other server is not performed !!! I still retrieve my TGT ticket in one server and I can't in the other one. Any help pleaze , I m blocked ! Thx for 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/d/optout.
Re: Memcached/repcached: the need for repcached
I found out we use it as some sort of temporary storage. So not actually as a layer in between. If one of the memcached nodes goes down we would loose this information (mostly only needed for a few minutes) and for compliancy we can't write this data to disk. Op woensdag 6 augustus 2014 08:13:40 UTC+2 schreef Hirotaka Yamamoto: > > Hi, > > memcached can be used for various purposes other than caching. > For instance, we store session data in our memcached clone ( > https://github.com/cybozu/yrmcds ). > > Thanks to its high performance, a single server can serve all (> 10 > millions) sessions. > However, if the server crashes, all customers will be forced to sign-out. > > Replication protects us from such disaster. > > -- > ymmt2005 > -- --- 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: Memcached/repcached: the need for repcached
I understand that in most cases you don't need this. However to me it doesn't look like a seperate project (as it's bound to memcached, and can't be used "standalone"). Actually more like an enhancement/feature. In that case distros would distribute the binarie packages without this capability built-in. But for someone who wants to use it he could just configure it through make and compile. Probably somebody at memcached kept this feature out for some (probably good) reason. Op dinsdag 5 augustus 2014 20:06:16 UTC+2 schreef LesMikesell: > > On Tue, Aug 5, 2014 at 10:45 AM, PenguinWhispererThe > > wrote: > > Hi all, > > > > I wonder what the added value for repcached > > is(http://repcached.lab.klab.org/). > > It replicates the objects to both configured nodes. So you can read the > > cached value on all nodes even if it was added through the memcached on > the > > other node. > > > > In the normal memcached there is a constant hash algorithm so you will > hit > > the correct server when reading a previously set value. > > When this server goes down I assume you just "cache-miss" and get your > data > > directly from the database and then cache it on another memcached node? > > Yes, that is the normal memcache approach, and depending on your hash > choice you can either 'just fail' for a portion of the hash range > until the node is back or rebalance across the remaining nodes. As > long as you have a reasonable large number of nodes and a reasonably > fast database you can tolerate having some nodes down some of the > time. > > > I would assume repcache would give some kind of HA however I don't see > how > > this can't be accomplished by the normal memcached. > > Ok, you loose cache but it will be cached on another node again. In that > way > > it actually seems like repcached adds overhead. > > It isn't necessary in the general case - which is probably why it is a > separate project. It might help if you have a small number of nodes or > a database that can't handle a flurry of cache misses. > > -- >Les Mikesell > lesmi...@gmail.com > -- --- 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: Memcached/repcached: the need for repcached
Not sure if that's the case. If it's repcached then you can read and write values to both nodes. So you have active-active. DRBD is a shared block device. However repcached/memcached is in memory so not sure what those 2 have to do with each other. Op dinsdag 5 augustus 2014 18:22:19 UTC+2 schreef rspadim: > > i think repcached is used with DRBD solutions > two servers, if one server get down the other 'hot server' take the > 'cluster' ip address and start services without recreating the cache, with > a low startup time between fail and hot server start > > > 2014-08-05 12:45 GMT-03:00 PenguinWhispererThe >: > >> Hi all, >> >> I wonder what the added value for repcached is( >> http://repcached.lab.klab.org/). >> It replicates the objects to both configured nodes. So you can read the >> cached value on all nodes even if it was added through the memcached on the >> other node. >> >> In the normal memcached there is a constant hash algorithm so you will >> hit the correct server when reading a previously set value. >> When this server goes down I assume you just "cache-miss" and get your >> data directly from the database and then cache it on another memcached node? >> >> I would assume repcache would give some kind of HA however I don't see >> how this can't be accomplished by the normal memcached. >> Ok, you loose cache but it will be cached on another node again. In that >> way it actually seems like repcached adds overhead. >> >> Another thought I had is that if one very frequently executed query gets >> a hash that is on for example memcache server X that all subsequent clients >> that need the same data will also be sent to server X. So more load will go >> to that server. >> Am I thinking right here? Is that the purpose of repcached? Maybe a >> workaround could be to just create a few hashes with the same data so you >> can be sure that those will approximately be balanced over the different >> memcached servers? >> >> Note that I never used memcached/repcached but I'm trying to understand >> if we actually need this in our organisation. There seems to be an issue >> with a segmentation fault and I want to make sure I don't spend a lot of >> time while there might be a better solution. Repcached isn't maintained >> anymore either. So maybe it's better to look at a long term solution. >> >> 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+...@googlegroups.com . >> For more options, visit https://groups.google.com/d/optout. >> > > > > -- > Roberto Spadim > -- --- 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: Memcached/repcached: the need for repcached
Hi, memcached can be used for various purposes other than caching. For instance, we store session data in our memcached clone ( https://github.com/cybozu/yrmcds ). Thanks to its high performance, a single server can serve all (> 10 millions) sessions. However, if the server crashes, all customers will be forced to sign-out. Replication protects us from such disaster. -- ymmt2005 -- --- 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: Memcached/repcached: the need for repcached
On Tue, Aug 5, 2014 at 10:45 AM, PenguinWhispererThe wrote: > Hi all, > > I wonder what the added value for repcached > is(http://repcached.lab.klab.org/). > It replicates the objects to both configured nodes. So you can read the > cached value on all nodes even if it was added through the memcached on the > other node. > > In the normal memcached there is a constant hash algorithm so you will hit > the correct server when reading a previously set value. > When this server goes down I assume you just "cache-miss" and get your data > directly from the database and then cache it on another memcached node? Yes, that is the normal memcache approach, and depending on your hash choice you can either 'just fail' for a portion of the hash range until the node is back or rebalance across the remaining nodes. As long as you have a reasonable large number of nodes and a reasonably fast database you can tolerate having some nodes down some of the time. > I would assume repcache would give some kind of HA however I don't see how > this can't be accomplished by the normal memcached. > Ok, you loose cache but it will be cached on another node again. In that way > it actually seems like repcached adds overhead. It isn't necessary in the general case - which is probably why it is a separate project. It might help if you have a small number of nodes or a database that can't handle a flurry of cache misses. -- Les Mikesell lesmikes...@gmail.com -- --- 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: Memcached/repcached: the need for repcached
i think repcached is used with DRBD solutions two servers, if one server get down the other 'hot server' take the 'cluster' ip address and start services without recreating the cache, with a low startup time between fail and hot server start 2014-08-05 12:45 GMT-03:00 PenguinWhispererThe < th3penguinwhispe...@gmail.com>: > Hi all, > > I wonder what the added value for repcached is( > http://repcached.lab.klab.org/). > It replicates the objects to both configured nodes. So you can read the > cached value on all nodes even if it was added through the memcached on the > other node. > > In the normal memcached there is a constant hash algorithm so you will hit > the correct server when reading a previously set value. > When this server goes down I assume you just "cache-miss" and get your > data directly from the database and then cache it on another memcached node? > > I would assume repcache would give some kind of HA however I don't see how > this can't be accomplished by the normal memcached. > Ok, you loose cache but it will be cached on another node again. In that > way it actually seems like repcached adds overhead. > > Another thought I had is that if one very frequently executed query gets a > hash that is on for example memcache server X that all subsequent clients > that need the same data will also be sent to server X. So more load will go > to that server. > Am I thinking right here? Is that the purpose of repcached? Maybe a > workaround could be to just create a few hashes with the same data so you > can be sure that those will approximately be balanced over the different > memcached servers? > > Note that I never used memcached/repcached but I'm trying to understand if > we actually need this in our organisation. There seems to be an issue with > a segmentation fault and I want to make sure I don't spend a lot of time > while there might be a better solution. Repcached isn't maintained anymore > either. So maybe it's better to look at a long term solution. > > 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/d/optout. > -- Roberto Spadim -- --- 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.
Memcached/repcached: the need for repcached
Hi all, I wonder what the added value for repcached is(http://repcached.lab.klab.org/). It replicates the objects to both configured nodes. So you can read the cached value on all nodes even if it was added through the memcached on the other node. In the normal memcached there is a constant hash algorithm so you will hit the correct server when reading a previously set value. When this server goes down I assume you just "cache-miss" and get your data directly from the database and then cache it on another memcached node? I would assume repcache would give some kind of HA however I don't see how this can't be accomplished by the normal memcached. Ok, you loose cache but it will be cached on another node again. In that way it actually seems like repcached adds overhead. Another thought I had is that if one very frequently executed query gets a hash that is on for example memcache server X that all subsequent clients that need the same data will also be sent to server X. So more load will go to that server. Am I thinking right here? Is that the purpose of repcached? Maybe a workaround could be to just create a few hashes with the same data so you can be sure that those will approximately be balanced over the different memcached servers? Note that I never used memcached/repcached but I'm trying to understand if we actually need this in our organisation. There seems to be an issue with a segmentation fault and I want to make sure I don't spend a lot of time while there might be a better solution. Repcached isn't maintained anymore either. So maybe it's better to look at a long term solution. 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/d/optout.
