Centos 7 Slow Resolve

Question

Depois de instalar o Centos 7, notei que as pesquisas de DNS para endereços salvos em / etc / hosts demoram muito tempo, aqui está o exemplo:

time curl -X get http://localhost

real    0m0.159s
user    0m0.004s
sys     0m0.005s

mas

time curl -X get http://127.0.0.1

real    0m0.005s
user    0m0.001s
sys     0m0.003s

Leva ~ 0,15 segundos para resolver "localhost" por cada solicitação.

Eu faço os mesmos testes em outro servidor na mesma rede com o Centos 6.5, mas "localhost" é tão rápido quanto "127.0.0.1"

    

Answer 1

O Red Hat Bug 1130239 - Diferença no desempenho de curvas entre RHEL6 e RHEL7 :

The libcurl library used an unnecessarily long blocking delay for actions with no active file descriptors, even for short operations.  This meant that some actions, such as resolving a host name using /etc/hosts, took an artificially long time to complete.  The blocking code in libcurl has now been modified so that the initial delay is short, and gradually increases until an event occurs.  Fast libcurl operations now complete more quickly.

Instale a nova versão do curl a partir da fonte:

git clone https://github.com/bagder/curl.git
cd curl
yum install libtool
./buildconf
./configure
make
make install