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zl-max-sockets-per-pool - the number of connections per pool (there are several pools working in the browser, common to all tabs);
zl-max-sockets-per-group - number of connections per domain;
zl-max-sockets-per-proxy - number of connections on the proxy;
zl-max-sockets-per-pool-ws - number of connections per pool for WebSocket;
zl-max-sockets-per-group-ws - number of connections per domain for WebSocket;
zl-max-sockets-per-proxy-ws - number of connections per proxy for WebSocket;
zl-used-idle-socket-timeout-s - idle inactive used socket lifetime (seconds);
zl-unused-idle-socket-timeout-s - lifetime of an inactive unused socket (seconds);
zl-close-idle-connection-interval-s - interval to clean up inactive sockets (seconds).
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