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tor
master
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#include <or.h>
Data Fields | |
| time_t | next_attempt_at |
| uint8_t | n_download_failures |
| uint8_t | n_download_attempts |
| download_schedule_bitfield_t | schedule: 8 |
| download_want_authority_bitfield_t | want_authority: 1 |
| download_schedule_increment_bitfield_t | increment_on: 1 |
| uint8_t | last_backoff_position |
| int | last_delay_used |
Information about our plans for retrying downloads for a downloadable directory object. Each type of downloadable directory object has a corresponding retry schedule, which can be different depending on whether the object is being downloaded from an authority or a mirror (want_authority). next_attempt_at contains the next time we will attempt to download the object. For schedules that increment_on failure, n_download_failures is used to determine the position in the schedule. (Each schedule is a smartlist of integer delays, parsed from a CSV option.) Every time a connection attempt fails, n_download_failures is incremented, the new delay value is looked up from the schedule, and next_attempt_at is set delay seconds from the time the previous connection failed. Therefore, at most one failure-based connection can be in progress for each download_status_t. For schedules that increment_on attempt, n_download_attempts is used to determine the position in the schedule. Every time a connection attempt is made, n_download_attempts is incremented, the new delay value is looked up from the schedule, and next_attempt_at is set delay seconds from the time the previous connection was attempted. Therefore, multiple concurrent attempted-based connections can be in progress for each download_status_t. After an object is successfully downloaded, any other concurrent connections are terminated. A new schedule which starts at position 0 is used for subsequent downloads of the same object.
| download_schedule_increment_bitfield_t increment_on |
does this schedule increment on each attempt, or after each failure?
| uint8_t last_backoff_position |
number of attempts/failures, depending on increment_on, when we last recalculated the delay. Only updated if backoff == 1.
| int last_delay_used |
last delay used for random exponential backoff; only updated if backoff == 1
| uint8_t n_download_attempts |
Number of (potentially concurrent) attempts to download the most recent object, since the last success.
| uint8_t n_download_failures |
Number of failed downloads of the most recent object, since the last success.
| time_t next_attempt_at |
When should we try downloading this object again?
| download_schedule_bitfield_t schedule |
What kind of object is being downloaded? This determines the schedule used for the download.
| download_want_authority_bitfield_t want_authority |
Is the download happening from an authority or a mirror? This determines the schedule used for the download.
1.8.13