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Is there a way to limit network.http.max-persistent-connections-per-server to 1? I tried it but Firefox still seems to open 2 simultaneous connections

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In about:config I changed "network.http.max-persistent-connections-per-server" from 6 to 1, but sniffing with Wireshark I can still see 2 simultaneous connections. Firefox Version: 56.0.1 (64-bit) OS: Windows 8.1 Pro x64

In about:config I changed "network.http.max-persistent-connections-per-server" from 6 to 1, but sniffing with Wireshark I can still see 2 simultaneous connections. Firefox Version: 56.0.1 (64-bit) OS: Windows 8.1 Pro x64

All Replies (5)

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jeanvst said

In about:config I changed "network.http.max-persistent-connections-per-server" from 6 to 1, but sniffing with Wireshark I can still see 2 simultaneous connections.

Hi  !

Just to make sure : after you changed the value of that preference, did you close and then restart Firefox  ?

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Happy112 said

jeanvst said
In about:config I changed "network.http.max-persistent-connections-per-server" from 6 to 1, but sniffing with Wireshark I can still see 2 simultaneous connections.

Hi  !

Just to make sure : after you changed the value of that preference, did you close and then restart Firefox  ?

Hi, thanks for the reply.

I did restart Firefox. There was some effect on the configuration, since the first capture showed 6 connections, and after the change, 2 connections.

I repeated the test today and got an interesting (or weird?) result. If the destination address is on LAN (eg 192.168.1.x), Firefox opens a single connection as desired. If the destination is on WAN (eg 200.x.x.x), Firefox opens 2 connections.

Is there any other parameter I should change?

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In the following article, could you expand the Prefetching section and disable:

  • Link prefetching
  • Speculative pre-connections

How to stop Firefox from making automatic connections

Modified by jscher2000 - Support Volunteer

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jscher2000 said

In the following article, could you expand the Prefetching section and disable:
  • Link prefetching
  • Speculative pre-connections
How to stop Firefox from making automatic connections

As suggested, I did the following changes: - network.prefetch-next = false - network.dns.disablePrefetch = true - network.http.speculative-parallel-limit = 0

However, Firefox is still making 2 connections.

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If you do not get an explanation here, you may want to file a bug.

https://bugzilla.mozilla.org/enter_bug.cgi