The Prefetch Plugin is not working

[stackexpress-jawed]

I am using Prefetch Plugin as per this doc - https://docs.trafficserver.apache.org/en/9.0.x/admin-guide/plugins/prefetch.en.html

But It’ not prefetching the objects.
Prefetch Pattern - --fetch-path-pattern=/(.*-)(\d+)(.*)/$1{$2+1}$3/

Prefetch Plugin Logs (confirms that plugin is loaded successfully)

[Aug 05 03:23:53.171] [ET_NET 12] DIAG: (prefetch) prefetch/plugin.cc:450:contHandleFetch() event: TS_EVENT_HTTP_TXN_CLOSE (60012)
[Aug 05 03:26:50.162] traffic_server DIAG: (prefetch) prefetch/configs.cc:86:init() processing --fetch-policy=simple
[Aug 05 03:26:50.162] traffic_server DIAG: (prefetch) prefetch/configs.cc:86:init() processing --fetch-path-pattern=/(.*-)(\d+)(.*)/$1{$2+1}$3/
[Aug 05 03:26:50.162] traffic_server DIAG: (prefetch) prefetch/pattern.cc:331:compile() compiling pattern:'(.*-)(\d+)(.*)', replacement:'$1{$2+1}$3'
[Aug 05 03:26:50.162] traffic_server DIAG: (prefetch) prefetch/configs.cc:86:init() processing --fetch-count=3
[Aug 05 03:26:50.162] traffic_server DIAG: (prefetch) prefetch/configs.cc:160:finalize() front-end: false
[Aug 05 03:26:50.162] traffic_server DIAG: (prefetch) prefetch/configs.cc:161:finalize() exact match: false
[Aug 05 03:26:50.162] traffic_server DIAG: (prefetch) prefetch/configs.cc:162:finalize() API header name: X-AppleCDN-Prefetch
[Aug 05 03:26:50.162] traffic_server DIAG: (prefetch) prefetch/configs.cc:163:finalize() next object header name: X-AppleCDN-Prefetch-Next
[Aug 05 03:26:50.162] traffic_server DIAG: (prefetch) prefetch/configs.cc:164:finalize() fetch policy parameters: simple
[Aug 05 03:26:50.162] traffic_server DIAG: (prefetch) prefetch/configs.cc:165:finalize() fetch count: 3
[Aug 05 03:26:50.162] traffic_server DIAG: (prefetch) prefetch/configs.cc:166:finalize() fetch concurrently max: 0
[Aug 05 03:26:50.162] traffic_server DIAG: (prefetch) prefetch/configs.cc:167:finalize() replace host name:
[Aug 05 03:26:50.162] traffic_server DIAG: (prefetch) prefetch/configs.cc:168:finalize() name space: default
[Aug 05 03:26:50.162] traffic_server DIAG: (prefetch) prefetch/configs.cc:169:finalize() log name:
[Aug 05 03:26:50.162] traffic_server DIAG: (prefetch) prefetch/fetch.cc:123:BgFetchState() initialized lock
[Aug 05 03:26:50.162] traffic_server DIAG: (prefetch) prefetch/fetch.cc:130:BgFetchState() initialized lock
[Aug 05 03:26:50.162] traffic_server DIAG: (prefetch) prefetch/fetch_policy.cc:40:getInstance() getting 'simple' policy instance, params: (null)
[Aug 05 03:26:50.162] traffic_server DIAG: (prefetch) prefetch/fetch_policy_simple.cc:29:init() initialized simple fetch policy

Logs when accessing contents - http://prefetch.cache.<mydomain>.com/texts/demo-1.txt

The following objects should be prefetched (but unable to fetch following objects)

• http://prefetch.cache.<mydomain>.com/texts/demo-2.txt
• http://prefetch.cache.<mydomain>.com/texts/demo-3.txt
• http://prefetch.cache.<mydomain>.com/texts/demo-4.txt

[Aug 05 03:29:33.192] [ET_NET 13] DIAG: (prefetch) prefetch/plugin.cc:450:contHandleFetch() event: TS_EVENT_HTTP_POST_REMAP (60017)
[Aug 05 03:29:33.192] [ET_NET 13] DIAG: (prefetch) prefetch/plugin.cc:272:appendCacheKey() cache key: /origin1.cdn.opspi.com/80/texts/demo-1.txt
[Aug 05 03:29:33.192] [ET_NET 13] DEBUG: <MIME.cc:2670 (mime_field_block_describe)> (http) V: "http://prefetch.cache.<mydomain>.com/texts/", V_LEN: 43,
[Aug 05 03:29:33.193] [ET_NET 13] DIAG: (prefetch) prefetch/plugin.cc:450:contHandleFetch() event: TS_EVENT_HTTP_CACHE_LOOKUP_COMPLETE (60015)
Referer: http://prefetch.cache.<mydomain>.com/texts/
Referer: http://prefetch.cache.<mydomain>.com/texts/
Referer: http://prefetch.cache.<mydomain>.com/texts/

[stackexpress-jawed]

No, not solved.

[moonchen]

Have you tried setting @pparam=--front=true?

[ywkaras]

Have you tried setting @pparam=--front=true?

No. Currently I am trying to get it to work for single tier. Would you set that for single tier?

[moonchen]

Have you tried setting @pparam=--front=true?

No. Currently I am trying to get it to work for single tier. Would you set that for single tier?

I believe so.

[ywkaras]

Following moonchen's suggestion, I was able to get the plugin to work: #8810 . But I still don't understand why it's needed.

[ywkaras]

For now, I'm going to assume that everyone is OK with using the front parameter, as used in this Au test: https://github.com/apache/trafficserver/blob/master/tests/gold_tests/pluginTest/prefetch_simple/prefetch_simple.test.py . If not, please reopen this issue.