Обсуждение: Postgres 11 beta - no JITing
Hello, I am trying to assess the benefits of the new JIT feature in Postgres 11. However I can't figure out how to enable it. I have a test server with "CentOS Linux release 7.5.1804" I installed the beta using: yum install https://download.postgresql.org/pub/repos/yum/11/redhat/rhel-7.4-x86_64/postgresql11-server-11.0-beta1_1PGDG.rhel7.x86_64.rpm yum install postgresql11 yum install postgresql11-server Then initdb and everything was up and running. I checked the installation: "show jit_provider" gives me: "llvmjit" "show jit" gives me: "on" pg_config reports that the beta was built with LLVM support. I see --with-llvm in the output as well as 'LLVM_CONFIG=/usr/lib64/llvm5.0/bin/llvm-config' But on my system there is no /usr/lib64/llvm5.0 So I ran "yum install llvm" which gave me: "llvm-libs-3.4.2-8.el7.x86_64" and "llvm-3.4.2-8.el7.x86_64" but still no /usr/lib64/llvm5.0) And installing clang, gave me: clang.x86_64 3.4.2-8.el7 The cost of my test query is around 250000 - so even with the default configuration I would expect JITing to jump in. As it didn't happen, I set jit_optimize_above_cost and jit_above_cost to 10, just to see what happens - still no JITing I have uploaded one sample plan: https://explain.depesz.com/s/aVj2 Is there anything I need to install or enable in addition to what I have described? I am not really experienced with managing a Linux system, so if I did some blatantly wrong things, please bare with me ;) Thanks Thomas
Hi, On 2018-06-05 13:45:26 +0200, Thomas Kellerer wrote: > Hello, > > I am trying to assess the benefits of the new JIT feature in Postgres 11. However I can't figure out how to enable it. > > I have a test server with "CentOS Linux release 7.5.1804" > > I installed the beta using: > > yum install https://download.postgresql.org/pub/repos/yum/11/redhat/rhel-7.4-x86_64/postgresql11-server-11.0-beta1_1PGDG.rhel7.x86_64.rpm > yum install postgresql11 > yum install postgresql11-server I suspect the issue is that you also need the postgresql11-llvmjit package. The LLVM support adds dependencies, so it's not included in the main package. > Then initdb and everything was up and running. > > I checked the installation: > > "show jit_provider" gives me: "llvmjit" > "show jit" gives me: "on" You can check whether support actually could be loaded with SELECT pg_jit_available(); Greetings, Andres Freund
Andres Freund schrieb am 05.06.2018 um 14:34: >> I am trying to assess the benefits of the new JIT feature in Postgres 11. However I can't figure out how to enable it. >> >> I have a test server with "CentOS Linux release 7.5.1804" >> >> I installed the beta using: >> >> yum install https://download.postgresql.org/pub/repos/yum/11/redhat/rhel-7.4-x86_64/postgresql11-server-11.0-beta1_1PGDG.rhel7.x86_64.rpm >> yum install postgresql11 >> yum install postgresql11-server > > I suspect the issue is that you also need the postgresql11-llvmjit > package. The LLVM support adds dependencies, so it's not included in the > main package. Ah, that was it, thanks. (It took me a while to figure out how to also install llvm-5.0 for Centos 7, but I finally managed)