Download - Varnish, the high performance valhalla?
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Kings of Code 2011
Varnish, the high performance valhalla?
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THE ENRISE RESTAURANT
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THE ENRISE RESTAURANT
∂ We want to prepare the best dishes
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THE ENRISE RESTAURANT
∂ We want to prepare the best dishes∂ With the best ingredients
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∂ Engineers are our top chefs!
THE ENRISE RESTAURANT
∂ We want to prepare the best dishes∂ With the best ingredients∂ To create a magical client experience!
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BEFORE WE START
WHO KNOWS RFC 2616?
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BEFORE WE START
WHO KNOWS HTTP?
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BEFORE WE START
WHO THINKS HE/SHE KNOWS
HTTP?
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∂ Wikipedia : Proxy
STANDARD PROXY
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∂ Wikipedia : Reverse proxy
REVERSE PROXY
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∂ Wikipedia : Reverse proxy
REVERSE PROXY
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∂ Wikipedia : Reverse proxy
REVERSE PROXIES
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∂ Wikipedia : Reverse proxy
REVERSE PROXIES
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∂ Wikipedia : Reverse proxy
REVERSE PROXIES
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∂ NOT a webserver!
WHAT IS VARNISH? (1)
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∂ NOT a webserver!
WHAT IS VARNISH? (1)
∂Caching reverse proxy
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∂ NOT a webserver!
WHAT IS VARNISH? (1)
∂Caching reverse proxy∂Load balancer
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∂ NOT a webserver!
WHAT IS VARNISH? (1)
∂Caching reverse proxy∂Load balancer∂Fail over system
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∂ NOT a webserver!
WHAT IS VARNISH? (1)
∂Caching reverse proxy∂Load balancer∂Fail over system∂HTTP Accelerator
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WHAT IS VARNISH? (2)
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WHAT IS VARNISH? (2)
∂ Originally built for a Norwegian newspaper
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WHAT IS VARNISH? (2)
∂ Originally built for a Norwegian newspaper∂ > 545k new hostnames in December 2010§NetCraft monthly survey
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∂ Massive growth in usage
WHAT IS VARNISH? (2)
∂ Originally built for a Norwegian newspaper∂ > 545k new hostnames in December 2010§NetCraft monthly survey
∂ Known users§Wikileaks§Facebook§Twitter§SlashDot
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∂ Scaling limitations currently unknown
WHAT IS VARNISH? (3)
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∂ Scaling limitations currently unknown
WHAT IS VARNISH? (3)
∂Designed for 64bit architecture
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∂ Scaling limitations currently unknown
WHAT IS VARNISH? (3)
∂Designed for 64bit architecture∂Highly scalable
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∂ Scaling limitations currently unknown
WHAT IS VARNISH? (3)
∂Designed for 64bit architecture∂Highly scalable§Varnish in front of Varnish(es)
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∂ Scaling limitations currently unknown
WHAT IS VARNISH? (3)
∂Designed for 64bit architecture∂Highly scalable§Varnish in front of Varnish(es)∂Perfect browser cache solution
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∂ Scaling limitations currently unknown
WHAT IS VARNISH? (3)
∂Designed for 64bit architecture∂Highly scalable§Varnish in front of Varnish(es)∂Perfect browser cache solution§Prevent those hard refresh calls!
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∂ Possible request paths
INTERNALS (1)
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∂ Optimal request path
INTERNALS (2)
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∂ Caching request path
INTERNALS (3)
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∂ Prevent caching
INTERNALS (4)
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∂ Bypassing Varnish
INTERNALS (5)
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∂ Errors or issueing restarts
INTERNALS (6)
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∂ Compiled to C when run
VARNISH CONFIGURATION LANGUAGE (1)
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∂ Compiled to C when run
VARNISH CONFIGURATION LANGUAGE (1)
∂ 11 subroutines (vcl_recv, vcl_hash, etc ...)
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∂ Compiled to C when run
VARNISH CONFIGURATION LANGUAGE (1)
∂ 11 subroutines (vcl_recv, vcl_hash, etc ...)∂ Backend(s)
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∂ Compiled to C when run
VARNISH CONFIGURATION LANGUAGE (1)
∂ 11 subroutines (vcl_recv, vcl_hash, etc ...)∂ Backend(s)∂ Directors (random, round robin, hash)
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∂ Compiled to C when run
VARNISH CONFIGURATION LANGUAGE (1)
∂ 11 subroutines (vcl_recv, vcl_hash, etc ...)∂ Backend(s)∂ Directors (random, round robin, hash)∂ Access control lists
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∂ Compiled to C when run
VARNISH CONFIGURATION LANGUAGE (1)
∂ 11 subroutines (vcl_recv, vcl_hash, etc ...)∂ Backend(s)∂ Directors (random, round robin, hash)∂ Access control lists∂ Saint and grace mode
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∂ Compiled to C when run
VARNISH CONFIGURATION LANGUAGE (1)
∂ 11 subroutines (vcl_recv, vcl_hash, etc ...)∂ Backend(s)∂ Directors (random, round robin, hash)∂ Access control lists∂ Saint and grace mode∂ Custom subroutines
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∂ Compiled to C when run
VARNISH CONFIGURATION LANGUAGE (1)
∂ 11 subroutines (vcl_recv, vcl_hash, etc ...)∂ Backend(s)∂ Directors (random, round robin, hash)∂ Access control lists∂ Saint and grace mode∂ Custom subroutines∂ Inline C
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∂ Compiled to C when run
VARNISH CONFIGURATION LANGUAGE (1)
∂ 11 subroutines (vcl_recv, vcl_hash, etc ...)∂ Backend(s)∂ Directors (random, round robin, hash)∂ Access control lists∂ Saint and grace mode∂ Custom subroutines∂ Inline C∂ Since v3.0 : VMODS
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∂ Cache images in vcl_recv
VARNISH CONFIGURATION LANGUAGE (2)
if (req.request == “GET” &&req.url ~ “\.(gif|jpg|jpeg|bmp|png|ico)$”) {unset req.http.cookie;set req.grace = 1m;return(lookup);
}
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∂ Remove Google Analytics in vcl_recv
VARNISH CONFIGURATION LANGUAGE (3)
if (req.http.cookie) { set req.http.Cookie = regsuball(req.http.Cookie,
"__utm.=[^;]+(; )?", ""); if (req.http.cookie ~ "^ *$") { remove req.http.cookie; }}
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∂ Multiple backend configuration
VARNISH CONFIGURATION LANGUAGE (4)
backend default { .host="192.168.1.10"; .port="8080"; .probe={ .url=”/test.php”; }}backend second { .host="192.168.1.20"; .port="8080";}
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∂ Load balanced 33 / 66 % config
VARNISH CONFIGURATION LANGUAGE (5)
director balance random { { .backend = default; .weight = 1; } { .backend = second; .weight = 2; }}sub vcl_recv { set.req.backend = balance; return(pass);}
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∂ Adding headers on response
VARNISH CONFIGURATION LANGUAGE (6)
if (obj.hits > 0) { #if hit add hit count set resp.http.X-Cache = "HIT-" obj.hits;} else { set resp.http.X-Cache = "MISS”;}
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VARNISHING WORDPRESS (1)
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VARNISHING WORDPRESS (1)
∂Siege on standard WordPress homepage
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VARNISHING WORDPRESS (1)
∂Siege on standard WordPress homepage§No Varnish
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VARNISHING WORDPRESS (1)
∂Siege on standard WordPress homepage§No Varnish§Default Varnish installation
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VARNISHING WORDPRESS (1)
∂Siege on standard WordPress homepage§No Varnish§Default Varnish installation§Custom VCL configuration
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∂ No Varnish
VARNISHING WORDPRESS (2)
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∂ No Varnish
VARNISHING WORDPRESS (2)
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∂ No Varnish
VARNISHING WORDPRESS (2)
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∂ Default Varnish
VARNISHING WORDPRESS (3)
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∂ Default Varnish
VARNISHING WORDPRESS (3)
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∂ Default Varnish
VARNISHING WORDPRESS (3)
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∂ Kill those cookies!!
VARNISHING WORDPRESS (4)
# Drop any cookies sent to WordPress.sub vcl_recv { unset req.http.cookie;}# Drop any cookies WordPress tries to send backsub vcl_fetch { unset beresp.http.set-cookie;}
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∂ Custom Varnish
VARNISHING WORDPRESS (5)
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∂ Custom Varnish
VARNISHING WORDPRESS (5)
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∂ Custom Varnish
VARNISHING WORDPRESS (5)
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OTHER PITFALLS
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OTHER PITFALLS
∂ Accept headers§application/vnd.kingsofcode.speakers+xml;§return “Vary: Accept” header
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OTHER PITFALLS
∂ Accept headers§application/vnd.kingsofcode.speakers+xml;§return “Vary: Accept” header∂ Accept-encoding header
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∂ Not specifically Varnish issues
OTHER PITFALLS
∂ Accept headers§application/vnd.kingsofcode.speakers+xml;§return “Vary: Accept” header∂ Accept-encoding header∂ Vary: User-Agent header
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∂ Very powerful for content assembly
EDGE SIDE INCLUDES (1)
∂Markup language∂Co-authored Akamai, IBM, Oracle & more∂Extensive features
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∂ Examples? http://esi-examples.akamai.com
EDGE SIDE INCLUDES (2)
∂ if ... else§<esi:choose><esi:when> ... <esi:otherwise>
∂ Variables§<esi:assign> and <esi:vars>
∂ Varnish implements only one feature!§<esi:include src=”uri” />
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∂ VCL config for ESI
EDGE SIDE INCLUDES (3)
if (req.url ~ "^/url/to/esi/snippets") { unset beresp.http.set-cookie;}## enable esi on header from backendif (beresp.http.enable-esi == "1") { set beresp.do_esi = true; //varnish 3.0
unset beresp.http.enable-esi;}
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∂ Where are the ESI’s?
EDGE SIDE INCLUDES (4)
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∂ Different TTL’s for content snippets
EDGE SIDE INCLUDES (5)
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∂ You can’t go without
TOOLS
∂Varnishstat∂Varnishsizes∂Varnishtop∂Varnishadm∂Varnishlog
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VARNISHLOG
∂ Log hits§varnishlog -o VCL_Call hit | grep RxURL∂ Log misses§varnishlog -i TxURL
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∂ Request of a gif image by client
VARNISHLOG
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∂ Request of a gif image by client
VARNISHLOG
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∂ Request of a gif image by client
VARNISHLOG
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∂ Request of a gif image by client
VARNISHLOG
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CAVEATS
∂ Unsuitable for 32 bit
∂ Beware of cookie monster applications
∂ Check your API design
∂ Avoid large files
∂ Minimize cookie usage in ESI
∂ No SSL support
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∂ Questions? Thank you!