Hello, menu thanks for your reply. I tried both post copy and converge but the live migrations is always very slow for applications servers like tomcat with java. The very strange behaviour is that if I migrate from compute node A to compute node B it takes more than 20 minutes. After that, if I migrate from compute B to compute A, it takes few seconds. I do not know if its is because dirty memory iscleaned during the first live migration. Live migration network si 10Gbs so I do not think the first live migration is affected by network performances. Ignazio Il giorno gio 4 ago 2022 alle ore 11:34 Fabian Zimmermann <dev.faz@gmail.com> ha scritto:
Hi,
take a look at:
https://docs.openstack.org/nova/latest/admin/configuring-migrations.html#adv...
esp. Auto-convergence and Post-copy
Fabian
Am Mi., 3. Aug. 2022 um 12:43 Uhr schrieb Ignazio Cassano <ignaziocassano@gmail.com>:
Hello All, I am looking for a solution to speed up live migration. Instances where ram is used heavily like java application servers, live
migration take a long time (more than 20 minutes for 8GB ram instance) and converge mode is already set to True in nova.conf.
I also tried with post_copy but it does not change. After the first live migration (very solow) if I try to migrate again it is very fast. I presume the first migration is slow because memory fragmentation when an instance is running on the same compute node for a long time. I am looking for a solution considering the on my computing node I can have a little ram overcommit. Any case I am increasing the number of compute nodes to reduce it. Thanks Ignazio