Tricky (?) questions about the LTM Web Acceleration
Hello! This is going to be a large body of text, so please have patience. Our developers has asked some excellent detailed questions about the LTM caching which I have been unable to fully answer. So I've been trying to read up on the web acceleration but I'm afraid I don't understand. First of all, let me state my theories/assumptions (would appreciate any corrections or validations): The cache size specified in the profile means the amount of RAM used per TMM core. So in a Viprion using 8 cores a cache size of 100Mb would mean that it uses 800Mb of RAM (providing that the cache is full). The F5 would try to get items from the other TMMs caches if possible before fetching content from the origin web server. The F5 cache size does not take meta-data about the items into account when calculating the limit. Ie. a cache filled with 10 million items of 1 byte would take up 10Mb plus the memory it takes to store the data about said items (this one was explained to me by F5 when our memory kept running out on our LB's). Items will be automatically evicted when they expire. If the cache is full, items accessed the longest time ago will be evicted first. I've been studying this solutions article in an attempt to understand how the statistics and caching works. Extract from the article: --------------------------------------------- Ltm::Web Acceleration Profile: wa-profile-rbk --------------------------------------------- Virtual Server Name N/A Cache Cache Size (in Bytes) *current cache size for this profile Total Cached Items *items in local cache Total Evicted Items *count of items that have been evicted from the local cache Inter-Stripe Size (in Bytes) *all the remote tmms cache Inter-Stripe Cached Items *remote tmms count of cached items Inter-Stripe Evicted Items *remote tmms count of cached items that have been evicted Cache Hits/Misses Count Bytes Hits 0 0 *tmm local cache served response Misses (Cacheable) 0 0 *tmm local cache items that match a rule set but are not in cache Misses (Total) 0 0 *tmm local cache items that either match or do not match rule set and are not served from cache Inter-Stripe Hits 0 0 *successful local access of remote caches Inter-Stripe Misses 0 - *unsuccessful local access of remote caches Remote Hits 0 0 *successful remote tmms accessing local cache Remote Misses 0 - *unsuccessful remote tmms accessing local cache My questions is: What does Inter-Stripe actually mean? What is the difference between "Misses (Cacheable)", "Inter-Stripe Misses" and "Remote Misses". When are "Inter-Stripe Misses" and "Remote Misses" triggered? Attaching my cache statistics for reference: Cache Cache Size (in Bytes) 1.3G Total Cached Items 526.2K Total Evicted Items 20.0M Inter-Stripe Size (in Bytes) 449.8M Inter-Stripe Cached Items 64.6K Inter-Stripe Evicted Items 67.8M Cache Hits/Misses Count Bytes Hits 737.2M 8.5T Misses (Cacheable) 184.9M 1.5T Misses (Total) 306.2M 2.6T Inter-Stripe Hits 611.5M 7.1T Inter-Stripe Misses 426.0M - Remote Hits 32.0M 209.6G Remote Misses 125.1M - Thanks for any answers/input or even questions. /Patrik
iRule RAM CACHE odd behaviour
Hi, I am trying to cache and serve some content from the static contents of my .Net app. I have enabled the Cache on the HTTP profile, and applied the following rule to my Virtual Server:- when HTTP_REQUEST { set hostname [string tolower [HTTP::host]] set uriadd [string tolower [HTTP::uri]] if { [TCP::local_port clientside] == "443" } { if { $hostname == "someURL.test.co.uk" } { if { !([class match [IP::remote_addr] equals CUST_IP_Addresses]) and !([class match [IP::remote_addr] equals MIC_IP_Addresses]) and !([class match [IP::remote_addr] equals private_net]) } { drop } else { CACHE::disable pool CUST-someURL.test.co.uk_443_POOL } } else { if { ( $uriadd ends_with ".js" ) || ( $uriadd ends_with ".pdf" ) || ( $uriadd ends_with ".css" ) || ( $uriadd ends_with ".jpg" ) || ( $uriadd ends_with ".png" ) || ( $uriadd ends_with ".gif" ) } { enable the cache CACHE::enable } else { disable the cache CACHE::disable } mobile site if { $hostname == "someAURL.test.co.uk" } { pool CUST-someAURL.test.co.uk_443_POOL } elseif { ($hostname ends_with "test.co.uk") } { pool CUST-www.test.co.uk_443_POOL } elseif { ($hostname ends_with "test1.co.uk") } { pool CUST-test1.co.uk_443_POOL } else { pool CUST-test2.co.uk_443_POOL } } ----------------------------------------------------- Handle HTTP requests } else { if { $hostname == "someURL.test.co.uk" } { if { !([class match [IP::remote_addr] equals CUST_IP_Addresses]) and !([class match [IP::remote_addr] equals MIC_IP_Addresses]) and !([class match [IP::remote_addr] equals private_net]) } { drop } else { CACHE::disable pool CUST-someURL.test.co.uk_80_POOL } } else { if { ( $uriadd ends_with ".js" ) || ( $uriadd ends_with ".pdf" ) || ( $uriadd ends_with ".css" ) || ( $uriadd ends_with ".jpg" ) || ( $uriadd ends_with ".png" ) || ( $uriadd ends_with ".gif" ) } { enable the cache CACHE::enable } else { disable the cache CACHE::disable } mobile site if { $hostname == "someAURL.test.co.uk" } { pool CUST-someAURL.test.co.uk_80_POOL } elseif { ($hostname ends_with "test.co.uk") } { pool CUST-www.test.co.uk_80_POOL } elseif { ($hostname ends_with "test1.co.uk") } { pool CUST-test1.co.uk_80_POOL } else { pool CUST-test2.co.uk_80_POOL } } } ----------------------------------------------------- Tidy up variables unset hostname uriadd } So i expect all assets that end in js, pdf, css, jpg, png, or gif to be cached and then served from the cache. however when i turn on log these cache hits in the local log, it lists the assets but says 0 cache hits for the identical assets over and over again. : 0 cache hits for document at www.bla.co.uk/Assets/bla/Images-css/btn-close.png : 0 cache hits for document at www.bla.co.uk/Assets/bla/products/H/O/N/HONIPUPB_AV2_st.jpg : 0 cache hits for document at www.bla.co.uk/Assets/bla/Images-css/right-tab-selected.png : 0 cache hits for document at www.bla.co.uk/Assets/bla/Images-css/left-tab-selected.png : 0 cache hits for document at www.bla.co.uk/Assets/bla/Images-css/bg-resultsmenu.png : 0 cache hits for document at www.bla.co.uk/Assets/bla/Images-css/bg-add-to-basket.png : 0 cache hits for document at www.bla.co.uk/Assets/bla/Images/btn-go.png We have pretty much exactly the same rule running for the site serving the CMS and these are clearly showing cache hits of more than 0. if anyone can explain what is happening that would be great. we use 10.2.3, and dont have webaccelerator. Many thanks
Using iControlREST to list entries in ramcache
I'm trying to build a bash script to query the F5 so that we can see what entries are on the ramcache profile. I am able to delete entries with: curl -sk -u $USERNAME:$PASSWORD -X DELETE but I can't find out how to do something like that but for getting info: curl -sk -u $USERNAME:$PASSWORD -X GET I see cryptic mentions online and in the docs that this is possible, but I can't figure it out. Am I going about this the wrong way?
Issues with HTTP/2 and web acceleration
Hi, I am testing HTTP/2 for a virtual server that already has a compression and web acceleration profile in use. HTTP/2 works fine when I add the relevant profile, although stylesheets fail to load. Instead of a stylesheet I get a "HTTP status code 000". I tried deleting the contents of the ramcache, but did not help. It only works when i remove the web acceleration profile from the virtual server. Has anyone experienced anything similar? Kind regards, Morten
how configured ramcache in Big-IP 5250
Hello people! i have a problem, i want to configure a ramcache but i am reading about it and i need to configure a ram cache with size of 400Mb but in the manual described a parameter called “Maximum Cache Size” in the profile of http but in my setting dont exist this parameter at least not in the web interface. I have a Big-Ip model 5250 . somebody have a idea ?
How to remove some object in ramcache
helo there, I am still new to using F5 Firewall, I want to ask is there any way or command to delete an existing object in the ram cache, but not the whole cache. Because I made some changes to certain files and just want to remove it in the cache so that changes can be seen directly on the client. I am using BIG IP 11.4.0 thank you and sorry for my bad english.
